EPA-66 0/2-73-010
December 1973
                       Environmental Protection Technology Series
   Treatment  Of Domestic Wastewater
   And  NSSC Pulp  And Paper  Mill  Wastes
                                    f
                                    I
SSE2
\
 CD
                                Office of Research and Development
                                U.S. Environmental Protection Agency
                                Washington. D.C. 20460

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             RESEARCH REPORTING SERIES
Research reports of the   Office  of  Research  and
Monitoring,  Environmental Protection Agency, have
been  grouped into five series.  These   five   broad
categories  were established to facilitate further
development  and  application   of   environmental
technology.   Elimination  of traditional grouping
was   consciously  planned  to  foster    technology
transfer   and  a  maximum  interface   in  related
fields.   The five series  are:

   1.  Environmental Health Effects Research
   2.  Environmental Protection Technology
   3.  Ecological Research
   fl.  Environmental Monitoring
   5.  Socioeconomic Environmental Studies

This  report has been assigned to the ENVIRONMENTAL
PROTECTION   TECHNOLOGY    series.    This    series
describes   research   performed  to  develop  and
demonstrate   instrumentation,    equipment     and
methodology  to  repair   or  prevent environmental
degradation from point and  non-point   sources  of
pollution.  This work provides the new  or improved
technology  required for  the control and treatment
of pollution sources to meet environmental quality
standards.
                   EPA REVIEW NOTICE

This report has been reviewed by the Office of Research ..ud
Development, EPA, and approved for publication.  Approval does
not signify that the contents necessarily reflect the views
and policies of the Environmental Protection Agency, nor does
mention of trade names or commercial products constitute
endorsement or recommendation for use.
  For sale by the Superintendent at Documents, U.S. QoTemment Printing Office, Washington, D.C. 2M02 - Frie* $1.40

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                                     EPA-660/2-73-010
                                     December  1973
   TREATMENT OF DOMESTIC WASTEWATER AND

      NSSC PULP AND PAPER MILL WASTES
                    By

               P. J. Farrell
                L. R. Heble
              A. G. Steuhser
Project No. 12130 DBF (formerly 11060 DBF)
          Program Element 1B2036
              Project Officer

            Edmond P. Lomasney
      Environmental Protection Agency
        1421 Peachtree Street, N.E.
          Atlanta, Georgia 30309
               Prepared for

    OFFICE OF RESEARCH AND DEVELOPMENT
   U.S. ENVIRONMENTAL PROTECTION AGENCY
          WASHINGTON, D.C. 20460

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                                   ABSTRACT
The Haniman Utility Board and the Mead Corporation made a study of the joint treatment
of primary clarified domestic waste and neutral sulfite semichemical (NSSC) pulp and paper
mill wastes. A pilot plant was constructed and operated from April, 1971 through March,
1972.

The most effective treatment scheme consisted of a biofilter (used as a roughing filter) and
an extended  aeration system. Color reduction was accomplished by massive lime and
chlorine additions due to the color's dependency on pH. Disinfection was optimum when
ammonia was mixed with the combined wastes prior to chlorination.

The BOD removal efficiency of the biofilter ranged from 3 to 45 percent. The BOD removal
efficiency of extended aeration ranged from 24 to 98 percent.

This report  was  submitted in fulfillment  of Research  and Development  Grant No.
11060-DBF between the Environmental Protection Agency and the Haniman Utility Board,
Harriman, Tennessee.

KeyWords: Domestic waste,  neutral sulfite  semichemical  (NSSC) pulp and  paper mill
           waste, pilot plant, primary clarification, biofiltration, intermediate clarification,
           extended aeration, color removal, disinfection.
                                      m

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                          TABLE OF CONTENTS

Section Number                                                     Page Number

                 Abstract                                                iii
                 Figures                                                 vi
                 Tables                                                 vii
      I          Conclusions                                              1
      II         Recommendations                                        2
      III        Introduction                                             3
      IV        Objectives                                               5
      V         The Pilot Plant                                           7
      VI        Wastewater Characterization                               19
      VII        Primary Treatment of NSSC Wastewater                    32
      VIII       Biofiltration                                             37
      IX        Extended Aeration Treatment                             41
      X         Final Clarification                                        64
      XI        Color Removal                                          68
      XII        Disinfection                                             77
      XIII       Design Considerations                                    85
      XIV       Acknowledgments                                        87
      XV        References                                             89
      XVI       Glossary of Terms                                       91
      XVII      Appendix                                              95

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                                FIGURES

Figure Number                                                      Page Number
    1          Waste Treatment Facilities                                 4
    2          Pilot Plant Sampling Points                                 8
    3          Overall View of the Pilot Plant during Startup
               Aeration Basin During Startup                              9
    4          Pilot Plant Flow Diagram:  Arrangement No.  1                11
    5          Pilot Plant Flow Diagram:  Arrangement No.  3                12
    6          Pilot Plant Flow Diagram:  Arrangement No.  4                13
    7          Clarified Domestic Waste BOD vs. Percent Occurrence          20
    8          Clarified Domestic Waste COD vs. Percent Occurrence          21
    9          Clarified Domestic Waste VSS vs. Percent Occurrence          22
    10         Clarified Domestic Waste Total Nitrogen (as N)
               Concentration vs. Percent Occurrence                        23
    11         Clarified Domestic Waste Total Phosphate (as PQ4 )
               Concentration vs. Percent Occurrence                        24
    12         Raw NSSC Waste BOD vs. Percent Occurrence                25
    13         Raw NSSC Waste COD vs. Percent Occurrence                26
    14         Raw NSSC Waste VSS vs. Percent Occurrence                27
    15         Raw NSSC Waste Total Phosphate (as PO4 ) vs.
               Percent Occurrence                                       28
    16         Clarified NSSC Waste BOD vs. Percent Occurrence             35
    17         Clarified NSSC Waste VSS vs. Percent Occurrence             36
    18         Biofiltration BOD Removal vs. BOD Loading                 39
    19         Extended Aeration, Arrangement No. 1: BOD
               Loading vs. Effluent BOD                                  43
    20         Extended Aeration, Arrangement No. 3: BOD
               Loading vs. Effluent BOD                                  45
    21         Extended Aeration, Arrangement No. 4: BOD
               Loading vs. Effluent BOD                                  48
                                     VI

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                          FIGURES (Continued)

Figure Number                                                     Page Number
    22         Alpha and Beta vs. Percent NSSC Waste Based
               on Flow                                               54
    23         Oxygen Transferred vs.  BOD Removed                       56
    24         Oxygen Uptake vs. BOD Removed                          60
    25         Excess Sludge Optimum Conditions vs.  BOD Removed         61
    26         Excess Sludge Optimum Conditions vs.  Influent VSS           62
    27         Final Clarifier BOD vs. TSS Removed                       66
    28         Final Clarifier Overflow Rate vs. Percent TSS Removed        67
    29         Color Removal and pH:  100 percent NSSC Waste             72
    30         Color Removal and pH: 50 percent NSSC + 50 percent
               Wastewater                                             73
    31         Color Removal and Lime + Chlorine: 100 percent
               NSSC Waste                                             74
    32         Color Removal and Lime + Chlorine:  50 percent
               NSSC + 50 percent Wastewater                             75
                                    VII

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                                 TABLES
Table Number                                                         Page Number
     1          Description of Sample Points                                14
     2          Pilot Plant Operation
               Arrangements and Schemes Description                       15
     3          Log of Significant Events in Operation of Pilot Unit            16
     4          Comparison of Hydraulic and Process Loadings                30
     5          Primary Treatment Data
               NSSC Waste Monthly Averages                               33
     6          Biofilter Operation Data with Primary Treatment              38
     7          Extended Aeration Results (July 14 - August 26, 1971)
               Arrangement No.  1                                         42
     8          Extended Aeration Results - (October  13, 1971 -
               March 2, 1972) Arrangement No. 3                          46
     9          Extended Aeration Results - (March 3  - 29, 1972)
               Arrangement No. 4                                         50
     10         Alpha and Beta vs. Percentage NSSC Waste                    53
     11         O2  Applied vs. BOD Removed                               55
     12         O2  Uptake — Aeration Basin Data                           58
     13         O2  Uptake vs. BOD Removed                                59
     14         Final Clarifier Performance (Monthly Average Data)            65
     15         Results of Color Removal Studies                            69
     16         Disinfection Studies — Coliform Baseline Determination         78
     17         Disinfection Studies — Application and  Sequence
               Evaluation                                                79
     18         Disinfection Studies — Application, Sequence, and
               Contact Time Evaluation                                    80
     19         Disinfection Studies — Application, Sequence, and
               Contact Time Evaluation                                    81
     20         Disinfection Studies — Effluent Coliform after
               Chlorination                                               82
     21         Disinfection Studies - Effluent Coliform after
               Chlorination                                               83
                                      vui

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                                   SECTION I

                                 CONCLUSIONS
The conclusions of this report were based upon data developed from the operation of the
Hairiman Utility Board pilot plant  over a one-year period. An extensive sampling and
analysis program conducted during the study provided the data to evaluate the pilot plant
performance under field conditions. The following are the conclusions reached during this
study.

         1.       As  NSSC loading increased from  40 — 90  percent, the
                  effluent BOD increased from 30-120 mg/1.

         2.       Primary clarification  of the NSSC wastes followed by high
                  rate biological filtration removed an average of 16 percent of
                  the  influent BOD  at  hydraulic  loadings  of 50  -  100
                  mgd/acre.

         3.       The biofilter — extended aeration combination proved to be
                  the most efficient treatment scheme.

         4.       High  NSSC to  domestic wastewater ratios  reduced  the
                  effectiveness of the optimum treatment scheme.

         5.       Both  primary and  secondary clarification improved  the
                  overall BOD removal efficiency.

         6.       Color was found to be pH dependent and required massive
                  lime  and chlorine  additions for effective removal. Lime
                  requirements would be approximately 194 tons per million
                  gallons of wastewater.

         7.       Maximum disinfection was achieved by addition of 40 mg/1
                  ammonia and  20  mg/1   chlorine.  Contact times  greatly
                  affected the degree  of disinfection. A five-minute contact
                  time  after  the ammonia  addition followed by a 15-minute
                  contact time after chlorination proved to be most effective.

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                                  SECTION II

                             RECOMMENDATIONS
As a result of this study, it is recommended that:

         1.        Primary clarification of the raw NSSC wastewater followed
                  by biofiltration of the combined NSSC-domestic wastewater
                  precede extended aeration of the wastewaters.

         2.        Greater than 90 percent NSSC for the combined wastewater,
                  based on BOD loading, should be avoided.

         3.        Disinfection can be best achieved by addition of ammonia
                  and chlorine.

         4.        Additional work is needed on lime recycle before massive
                  lime treatment  is considered as an economical means of color
                  removal.

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                                   SECTION III

                                 INTRODUCTION
A joint treatment study of domestic wastewater and neutral sulfite semichemical (NSSC)
pulp and paper mill wastes was conducted with the aid of an Environmental Protection
Agency Research and Development Grant (11060-DBF). The main purpose of the study was
the  feasibility  of a joint treatment scheme.  Joint treatment could  provide a means  for
regionalization of treatment and economy of scale.

A pilot plant was constructed adjacent to the Harriman Utility Board, Harriman, Tennessee
primary wastewater treatment plant. The pilot plant, completed in February of 1971,
provided a means of evaluating a variety of hydraulic and organic loadings under controlled
conditions. The pilot plant was operated from April, 1971 through March, 1972.

The NSSC waste was available at the pilot plant site (see Figure 1) from  the Mead
Corporation, Harriman, Tennessee.  The primary wastewater effluent was channeled from
the Harriman wastewater treatment plant to the pilot plant.

A short appendix covering the pilot plant's operational parameters and results will be made
available upon request.

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         TREATMENT FACILITIES
TREATMENT OF DOMESTIC WASTEWATER
AND NSSC PULP AND PAPER MILL WASTES
                        FIGURE 1

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                                    SECTION IV

                                   OBJECTIVES
The general objectives of this project were to construct and operate a pilot plant, evaluate
the treatability of combined  wastewater from  domestic sources and an integrated neutral
sulfite semichemical (NSSC) pulp and paper mill, and develop design criteria applicable to
its treatment.

The detailed objectives include the following:

         1.       Establish   design  criteria,   operating  parameters   and
                  efficiencies  of the following secondary  processes for the
                  treatment of combined municipal and NSSC pulp and paper
                  mill wastewater in varying proportions:

                  (a)       Extended aeration
                  (b)       High-rate biological filtration
                  (c)       High-rate biological  filtration followed
                            by extended aeration

         2.       Investigate the effects of a varying ratio of NSSC wastes to
                  municipal wastewater on the above treatment processes.

         3.       Determine the supplemental nutrient requirements  for the
                  above treatment processes.

         4.       Evaluate  the  requirement for primary clarification of NSSC
                  wastes in conjunction with the above treatment processes.

         5.       Investigate and evaluate the role of secondary clarification in
                  the  overall reduction of biochemical oxygen demand (BOD)
                  in the above treatment processes.

         6.       Investigate color reduction of the combined NSSC-municipal
                  wastewater by the massive lime dosage technique  and other
                  methods.  Evaluate   color  reduction  methods  in   the
                  laboratory.

         7.       Investigate    the   disinfection  of   combined   municipal
                  wastewater  and  NSSC  pulp  and  paper mill  wastes after
                  treatment by the proposed methods. Investigatory  work is to
                  include laboratory bench scale tests to compare efficiencies

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and costs of various agents for reducing the concentration of
coliform group  organisms in  treated  wastewater.  Such
common agents  as  chlorine  and  chloramines  are to  be
employed.  Investigate the effects of concentration, contact
time,  etc., during the  bench  tests to establish optimum
conditions for acceptable levels of bacterial reduction.

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                                   SECTION V

                                THE PILOT PLANT

                                    Description
A flow diagram of the pilot plant as constructed is shown in Figure 2. A photograph of the
overall pilot unit is shown in Figure 3. The pilot unit was sized to treat 15 to 200 gallons per
minute (gpm) of combined NSSC-municipal wastewater.

As indicated  in the process flow diagram, the NSSC wastes were clarified in a primary
clarifier prior to being combined with the municipal wastewater. The primary clarifier is
11.5 feet in diameter and has a 7.1-foot sidewater depth (SWD). Primary sludge should be
withdrawn at least once every hour.

A double weir box was used to measure the clarified NSSC and municipal wastewater. A
1,400-gallon capacity  blend tank  was used to combine the wastewater. Nitrogen  and
phosphorus, as needed, were pumped into the blend tank by a controlled volume pump
(20.8 gph maximum capacity) from a 335-gallon nutrient feed tank.

The blended waste was pumped by a 150 gpm transfer pump to a weir box on top of the
trickling filter which is 39 feet tall and 9 feet in diameter. This weir box measured the flow
of raw waste to the trickling filter or to the aeration basin.

The trickling filter was a high rate trickling  filter with approximately 1,200 cubic feet of
synthetic media. A separate weir box was used to measure the recycled flow to the trickling
filter. An intermediate clarifier, 15 feet in diameter and with a 14.4-foot SWD, was used to
clarify the  trickling filter effluent. The sludge removed from the intermediate clarifier was
discharged to a waste sump and the supernatant was discharged to the aeration basin.

The activated sludge  system was comprised of an aeration basin and  final clarifier.  The
aeration basin had a 120,000-gallon capacity and was equipped with a  15 hp blower-draft
diffused tube aeration system. A photograph of the aeration basin is also shown in Figure 3.

A wen- box was provided to measure recirculated flow from the final clarifier to the aeration
basin. The  clarifier had a 15-foot diameter and 13-foot SWD, and was equipped with a 180
gpm return sludge pump. The pump was used to return the sludge to the aeration basin weir
box or waste sludge to the waste sump.

Effluent from the final clarifier was chlorinated in a 4,200-gallon capacity chlorine contact
chamber equipped  with a 3.2 gph maximum  capacity  controlled  volume pump for

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                EXISTING
               EFFLUENT
               WET WELL
                 INDUSTRIAL     DOMESTIC
                 WEIR BOX\    /"WEIR BOX
                                                       PUMP a- v.
                                              NUTRIENT      J	
                                              FEED TANKX    O
                                    NS8C
                                   WASTE
                                  CLARIFIER
                      WASTE
                     
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'

                OVERALL VIEW OF THE PILOT PLANT DURING STARTUP
                  PILOl  PLANT  AERATION  BASIN DUUING STARTUP
                                                  TREATMENT OF DOMESTIC WASTEWATER
                                                  AND NSSC PULP AND PAPER MILL WASTES
                                                                             FIGURE   3

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disinfection. Ammonia feed facilities were also available for final effluent disinfection. The
waste sump was a 2,000-gallon tank with a 200 gpm capacity pump which pumped the
waste to an existing effluent wet well.

Piping and valves  were provided to bypass the primary clarifier, the trickling filter, the
intermediate  clarifier and  aeration basin,  the  final clarifier and  the chlorine  contact
chamber.  This  added flexibility was required to evaluate the performance of the  unit
processes in the pilot system.
                                     Operation

The pilot plant was operated under three arrangements, Nos. 1,3, and 4 (see Figures 4,5,
and 6). Arrangement 1 consisted of primary clarification of the NSSC waste before blending
with the clarified  domestic wastewater. The mixture  was then admitted to the aeration
basin,  final  clarifier and the chlorination chamber. Arrangement 3 consisted of primary
clarification of the NSSC waste before blending with domestic wastewater. The mixture was
then fed to the biofilter where the organic and hydraulic loadings were varied. From the
biofilter, the wastewater went to an intermediate clarifier, then into the aeration basin, final
clarifier and the chlorination chamber. Arrangement 4 was identical with Arrangement 3
with one exception: the NSSC waste was not subjected  to primary clarification before being
introduced to the biofilter.

Arrangement 2 was discontinued in the study when it was determined that supplemental
nutrient addition was not necessary for adequate treatment of the combined wastes. These
arrangements were divided  into a total of 14 schemes (see Table 2). Figure 2 shows the
sampling points used in monitoring the operation of the unit  and Table 1  describes the
sampling points. The sampling cocks necessary for sample draw-off should be located on the
top of the pipes to avoid solids that will settle to the bottom of the pipes. This would
reduce the  chances of settled  solids influencing the  analyses  of the  sample. The
arrangements and schemes described in Table 2 were evaluated by monitoring these sample
points under the variety of organic and hydraulic loadings indicated.

A chronological summary of major events during the operation  of the pilot system is given
in Table  3. This shows times of changes in the arrangements and schemes of the unit and
significant occurrences affecting its operation.
                                     10

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                INDUSTRIAL    DOMESTIC
                WEIR aax\   /WEIH BOX
                                                                                                                                                          CLg CONTACT

                                                                                                                                                           CMAMB
tn
                                                                                                                                       PILOT PLANT FLOW DIAGRAM:

                                                                                                                                            ARRANGEMENT NO. 1
                                                                                                                                   TREATMENT OF DOMESTIC WASTEWATER
                                                                                                                                   AND NSSC PULP AND PAPER MIL.L WASTES

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     BY-PABB^    1  ,

9L
CLa CONTACT
                                                     PILOT PLANT FLOW DIAGRAM:
                                                          ARRANGEMENT NO.3
                                                  TREATMENT OF DOMESTIC WASTEWATER
                                                  AND NSSC PULP AND PAPER MILL WASTES

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                  EXISTING
                 EFFLUENT
                 WET WELL
                   IIMOUSTRIAL     DOMESTIC
                   WEIR BOX\    /WEIR BOX
                                                                                                                      WEIR
                                                                                                                      (BOX
                                                                                                                       I              - BY- PASS
                                                                                                                    	*	1 V-txj	C.	
                                                                                                                                                                       FINAL

                                                                                                                                                                    CLARIFIER
                                                                                                                                                                                            CLB CONTACT

                                                                                                                                                                                            (CHAMBER
(73
                                                                                                                                                                           PILOT PLANT FLOW DIAGRAM:
                                                                                                                                                                                  ARRANGEMENT NO. 4

                                                                                                                                                                       TREATMENT OF DOMESTIC WASTEWATER
                                                                                                                                                                       AND NSSC PULP AND PAPER MILL WASTES

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                     TABLE 1

        DESCRIPTION OF SAMPLE POINTS
Sample
 Point	Description
  S-1                   NSSC Waste Influent

  S-2                   Clarified Domestic Wastewater Influent

  S-3                   NSSC Waste Clarifier Effluent
                       (Influent to Blend Tank)

  S-4                   Recycle From Blend Tank

  S-5                   Influent to Biofilter From Blend Tanks

  S-6                   Influent to Intermediate Clarifier From Biofilter

  S-7                   Influent Aeration Basin From Intermediate Clarifier

  S-8                   Influent Final Clarifier From Aeration Basin

  S-9                   Final Clarifier Effluent

 S-10                  Clj Contact Chamber Effluent

 S-11                   Recycle From Final Clarifier to Aeration Basin

 S-12                  Sludge From Intermediate Clarifier

 S-13                  Sludge From Final Clarifier

 S-14                  Sludge From Primary NSSC Waste Clarifier
                     14

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                                  TABLE 2
                          PILOT PLANT OPERATION
                ARRANGEMENTS AND SCHEMES DESCRIPTION
Arrangement         Scheme
  Number	Number	Description
     1                  1            Nutrient Optimization
     1                  2            MLSS Optimization - 300 mg/l
     1                  3            MLSS Optimization - 400 mg/l
     1                  4            MLSS Optimization - 2,000 mg/l
     1                  5            Waste Ratio Optimization - 63% NSSC, 37% DS
     1                  6            Waste Ratib Optimization - 95% NSSC, 5% DS
     3                 9            Hydraulic Loading to Biofilter Optimization
     3                 10           Hydraulic Loading to Biofilter Optimization
     3                 11           Hydraulic Loading to Biofilter Optimization
     3                 12           Organic Loading of Biofilter Optimization —
                                   500# BOD/cu ft
     3                 13           Organic Loading of Biofilter Optimization —
                                   750# BOD/cu ft
     3                 14           Waste Ratio Optimization - 95% NSSC, 5% DS
     3                 15           Waste Ratio Optimization - 100% NSSC, 0% DS
     4                 16           Effect of Primary Clarification —
                                    Raw NSSC Waste Used
                                   15

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                                                     TABLE 3
                           LOG OF SIGNIFICANT EVENTS IN OPERATION OF PILOT UNIT
Date

2/15/71

4/1/71


5/26/71


5/27/71


7/13/71


7/19/71


8/8/71

9/10/71
                    Event

Construction completed

Arrangement 1, Schemes 1 and 2 started
Arrangement 1, Scheme 3 started
Arrangement 1, Scheme 4 started
Arrangement 1, Scheme 5 started
Arrangement 1, Scheme 6 started
                  Remarks
An excess of nutrients in the raw waste prevented
determination of optimum nutrient levels •

VSS analyses using glass filters were initiated at all
sample points.

Sludge return from final clarifier changed to an
intermittent basin.

Soluble BOD analyses replaced total BOD in efflu-
ent monitoring.

MLSS of aeration basin increased to 4,000 mg/1 by
addition of anaerobic digester sludge.

NSSC to municipal wastewater ratio was varied.

High proportion of NSSC to municipal wastewater
caused removal efficiency to drop considerably so
Schemes 7 and 8 were abandoned. Changeover to
grab sampling at selected sample points was started.

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                                                TABLE 3 (Continued)

                           LOG OF SIGNIFICANT EVENTS IN OPERATION OF PILOT UNIT
Date

10/2/71



11/4/71


11/18/71

12/24/71
1/10-
1/12/72
1/20/72


1/25/72


2/11/72

2/12/72
                     Event

Arrangement 3, Scheme 9 started



Arrangement 3, Schemes 10 and  11 started


Arrangement 3, Scheme 13 started
Arrangement 3, Scheme 14 started
Arrangement 4, Scheme 15 started
                  Remarks

Acclimation period was allowed for growth on the
biofilter. Laboratory oxygen studies completed
and disinfection studies started.

Schemes 10 and 11 were run together because of
difficulty in controlling the hydraulic loading.

Difficulties remained in controlling the MLVSS.

Intermediate clarifier sludge concentrator was shut
down due to mechanical difficulties.

Air blower filter was dirty causing low air delivery
to aeration basin. Filter was cleaned and normal
operation resumed.

Some mechanical problems in aeration basin and
biofilter were cleared up.

Tap water had to be added to the NSSC waste in
order to get the biofilter distribution arm rotating.
                                                 Air blower filter cleaned again due to low air delivery
                                                 to aeration basin.

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00
Date

2/14/72


3/1/72


3/3/72

3/6/72


3/15/72

3/20/72
                                                            TABLE 3 (Continued)

                                        LOG OF SIGNIFICANT EVENTS IN OPERATION OF PILOT UNIT
                                                     Event
                                 Arrangement 4, Scheme 16 started
                  Remarks

Sump pump clogged with sludge and failed to run
for undetermined time.

Sloughing off of solids from biofilter resulted in
sharp rise in solids at Station 6.
Municipal wastewater flow to blend tank reduced
due to overflow.

Air blower filter cleaned again.

Dilution ratio used in disinfection studies changed
to lower value.

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                                  SECTION VI

                      WASTEWATER CHARACTERIZATION
Samples of the clarifier domestic waste and raw  NSSC waste were collected by  plant
personnel and analyzed at the site. The data were summarized and evaluated statistically.
Subsequent subsections describe the results of these evaluations.
                           Clarified Domestic Wastewater

The BOD, COD, VSS, total nitrogen and total phosphate data from April, 1971, through
March, 1972, were statistically evaluated.  Figures 7, 8, 9, 10 and  11  give the respective
results of these analyses. The evaluations  showed that constituents were present in  the
following geometric mean concentrations:

                Parameter                                Concentration (mg/1)

       BOD                                                    133
       COD                                                    360
       VSS                                                      54
       Total Nitrogen (as N)                                       24
       Total Phosphate (as PO4)                                    26


All values for BOD referred to in  this report are based upon standard  5-day, 20°C.  test
procedures.

The other constituents of pH, temperature, total solids, settleable solids, etc., fell within the
ranges for domestic wastewater. The pH varied from 6.5 to 7.5, the total solids ranged from
150 to 690 mg/1, and  temperature was from 9° to 29° C. depending upon the season. From
the characterization data, it can be  seen that the domestic wastewater handled by the pilot
unit was typical of a clarified domestic wastewater.
                                 Raw NSSC Waste

A summary of statistical analyses of constituents in the raw NSSC wastewater is given in
Figures 12 through 15. These  analyses include data for the period  from October,  1971,
through March, 1972.

The data were evaluated  for the months of October through March because these results
were more representative of the  waste treated by the pilot unit.  The months of April
through September were  atypical because the NSSC raw wastewater sampling point (from
April to October) was located where it gave erroneously high solids. This location was
changed at the end of September, 1971.

                                    19

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-------
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-------
Analysis of waste constituents indicated the following geometric mean concentrations:

                Parameter                                Concentration (mg/1)

       BOD                                                   1,850
       COD                                                   8,200
       VSS                                                     800
       Phosphate (as PO4)                                        8.6

The BOD and COD values were considerably higher than those for the domestic waste. Since
the COD and  BOD were not filtered, the results reflected oxygen demand due to  both
soluble organics and suspended solids in the wastewater.  The high volatile suspended solids
were due primarily to the presence of cellulose fibers in the pulp and paper mill wastewater.

The relatively high BOD of the NSSC wastewater and low BOD of the clarified domestic
wastewater resulted in high industrial process loadings  to the pilot system. Table 4 shows a
comparison of hydraulic loadings and corresponding  process loadings. The basis for the
comparison was  the geometric mean BOD for the NSSC wastewater and the municipal
wastewater, or a  1,850 and  135 mg/1 BOD for the industrial and domestic wastewaters
before blending. It can be  seen that  on the basis  of equal hydraulic  loadings that a
considerably higher industrial process loading is handled by the plant.

The other constituents fall in the following ranges:

                Constituent                          Concentration (mg/1) *

       pH                                                6.3  - 7.7
       Total Solids                                        7,670 - 18,300
       Settleable Solids                                    10-900
       Temperature (° C.)                                  17-41
       Ammonia Nitrogen  (as NH3)                         nil — 35.0
       Nitrate Nitrogen (as NO3 )                           nil - 40.0
       Organic Nitrogen (as N)                             9.8  - 194.0

*Except pH and temperature

It is  seen that the wastewater  temperature  and  pH did not vary appreciably  due to
consistent operation of the paper mill process (see Table  A-2 in the Appendix). In addition,
there  were no reported incidents during the  study of accidental  spills which could have
upset  the pH. Nitrogen levels were more than sufficient to satisfy nutrient requirements.

Color data from laboratory studies indicated the raw NSSC waste had a color of 24,000
APHA units. At this color level, the waste was very dark brown and  extremely turbid.
                                     29

-------
                                TABLE 4

                       COMPARISON OF HYDRAULIC
                         AND PROCESS LOADINGS
        Hydraulic Loading
        Percent of Total
  NSSC
Wastewater
 Clarified
 Domestic
Wastewater
                              Process Loading
                              Percent of Total
  NSSC
Wastewater
 Clarified
 Domestic
Wastewater
    1

   10

   50

   75

   90
   99

   90

   50

   25

   10
   12

   42

   93

   98
   88

   58

    7

    2
                                30

-------
In summary, wastewater characterization indicated relatively high concentrations of volatile
suspended solids,  BOD and  COD, and showed an adequate amount of phosphorus and
nitrogen  nutrients for biological treatment. The  pH was within  limits for biological
treatment (6 to 9), but the color was very dark.
                                      31

-------
                                  SECTION VII

                 PRIMARY TREATMENT OF NSSC WASTEWATER
The primary treatment of the raw NSSC wastewater was accomplished by settling the pulp
and paper solids and removing the sludge from the primary clarifier. The unit was operated
throughout most of the study from February, 1971, to March, 1972, and its performance
was based upon an evaluation of some of the operational data described in the following
subsections.
                                    Operation

The raw NSSC wastewater flowed from the influent weir box by gravity through a four-inch
cast iron pipe. The flow depended upon the pilot unit's requirements and was controlled by
a throttling valve. Sludge was collected by rakes in the hopper bottom clarifier, and it was
withdrawn periodically through an eight-inch pipe at the bottom of the clarifier to the waste
sump. At times during the study, heavy fiber paper solids created plugging problems and
caused some solids carry-over in the final effluent.

Normally, the raw NSSC wastewater had high concentrations of suspended paper solids (350
to 4,500 mg/1). In addition, there were considerable amounts of unsettleable dissolved and
suspended volatile solids which contributed to the total BOD and COD of the wastewater.
The temperatures were  usually higher than the domestic wastewater and did  not fluctuate
significantly with ambient temperature changes. This was due to the constant operation of
the pulp and paper mill  and as a  result, temperature was not a major consideration in
evaluating the efficiency of the clarifier.

Grab samples were collected  at  the  sample points shown in Table 1 and Figure 2.  An
evaluation of the data from the influent sample point from May, 1971, through September,
1971, resulted in a change in location of that sample collection station. For that time
period, the samples were collected  at a location which gave erroneously high suspended
solids results. To remedy this, the sampler was changed to a more suitable location for the
balance of the study.
                                   Performance

Performance of the primary clarifier was based upon the removal of BOD, COD and VSS at
various overflow  rates, detention times and solids loading rates. The primary settling data
are averaged and  summarized in Table 5; the individual data are given in Tables A-2 and A-3
of the Appendix.
                                   32

-------
                                                                TABLES

                                     PRIMARY TREATMENT DATA - NSSC WASTE MONTHLY AVERAGES*



Month
October
November
December
January
February
March
Average


Flow
(GPD)
22,000
16,600
28,600
26,500
23,400
17,400
22,400
Influent
Volatile
Suspended
Solids
(mg/1)
1,370
925
1,385
665
865
440
940
Percent Removal1
by Sedimentation
Influent
BOD
{mg/D
1,620
1,945
2,050
1,890
1,825
1,635
1,825
Influent
COD
(mg/1)
9,145,
9,320
8,510
7,240
8,660
7,140
8,335
Water
Temperature
(°F.)
92
81
79
66
73
80
79
Volatile
Suspended
Solids
62
50
45
76
70
69
62


BOD
-17
-10
0
-21
-10
-9
•11


COD
8
10
-5
-15
13
13
4
Detention
Time
(hr)
7.0
9.5
5.3
5.9
6.4
6.6
6.8
Sedimentation
Overflow
Rate
(GPSFPD)
254
192
330
306
270
201
254

Solids
Loading
(Ib/sq ft)
3
2
4
2
2
, 1
2
April and May data omitted due to plant start up
June to October data omitted due to change in sampling procedure
1 Negative values indicate increases in BOD and COD concentrations due to sedimentation

-------
The detention time and overflow rate calculations were based on the volume as calculated
from the sidewater depth and inside diameter of the clarifier. For example, an inflow of
22,000 gpd is calculated  to give 6.5 hours detention time with an overflow rate of 254
gpd/sq ft. The corresponding weir overflow is 67 gpd/lin ft.

Evaluations  based upon   statistical analyses  before and  after clarification are shown
graphically in Figures 12, 14, 16 and 17. For BOD  and  VSS analyses of the influent and
effluent, the average values were determined as follows:


                              Geometric Mean (mg/1)

                                                                           Percent
Parameter                Influent                Effluent                   Removed

  BOD                     1,950                 1,700                      13
  VSS                       800                   450                      44
A comparison based upon monthly average calculations (see Table 5) showed reductions of
62 percent for volatile suspended solids and an increase in BOD across the primary clarifier.
The COD was reduced an average of four percent and showed some decrease in organics.

The performance evaluations were difficult to determine due to variations in the data for
the different detention times and overflow rates.  Inconsistent data were due partially to
solids overflow when the sludge drawoff line was plugged by paper fibers. Also, variations in
performance were caused by the high percentages of unsettleable solids which contributed
to the BOD and COD. The volatile suspended solids were reduced an average of 44 to 62
percent for the detention times and overflow rates tested.
                                    34

-------
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-------
                                  SECTION Vffl

                                BIOFILTRATION
The biofiltration process unit included a high rate trickling filter packed with synthetic
media and an intermediate clarifier with recirculation. This unit was operated from October,
1971, through March,  1972. The performance was rated according to data collected from a
sampling program during this period.
                                    Operation

For the first six  to  eight weeks of operation the biofilter developed a growth and was
allowed to acclimate to the wastewater.  Samples were collected from  sample points as
indicated in Table 1 and  Figure 2. Only the data collected after the first six weeks of
operation was used in the performance evaluation. During the study  the NSSC wastewater
percentage  ranged from  70 to  100 percent.  At  the  times when 100  percent  NSSC
wastewater was used some tap water was introduced to assure proper  operation of the
trickling filter distribution arm.
                                   Performance

Table 6 provides weekly average operating data for the biofiltration process. Of particular
importance is the data on process loading. A comparison of normal high rate filter loading
and that experienced by the biofilter in this study is as follows:

                                   Hydraulic Loading            Organic Loading
     Biofilter Description               (mgd/acre)              (Ib BOD/1,000 CF)

Normal High Rate Biofilter                10 - 30                   80-100
Pilot Plant Biofilter                       48-102                  100-400
The data in  Table  6  also shows the rather  narrow temperature  range  the biofilter
encountered. For the period of data evaluation, the high temperature was 20° C. with an
average of 16° C. Due to the relatively narrow temperature range, the standard temperature
correction factor (Eckenfelder, 1966) for biofilters was not applied.

The BOD organic loading (pounds per day per thousand cubic feet filter media) was plotted
versus the BOD removed (ppd) as shown in Figure 18. This figure shows clearly that primary
treatment of the raw NSSC waste improved the BOD removal efficiency. As an example,
                                    37

-------
oo
                                                                              TABLE 6
                                                         BIOFILTER OPERATION DATA WITH PRIMARY TREATMENT
TcmDentim
Week of
10/I01
io/i7*
10/241
10/31 1
11/71
11/14
11/21
11/28
12/5
12/12
12/19
12/26
1/2
1/9
1/16
1/23
1/30
2/6
2/13
2/20
2/27
Average
°F.
_
79
77
73
66
72
66
64
66
68
66
66
55
68
63
59
52
54
54
54
59
62
°C

26
25
23
19
22
19
18
19
20
19
19
13
20
17
15
11
12
12
12
15
16
Process Loading
qb/day/l.OOOft3)
BOD COD
290 2
360
370
200
200
180
465 2
420
325
450
375
435 3
510
505
390
95
120
115
90
100
75
291

1,740
1,190
690
1,050
.6802
1.3402
1,680
1,250
1,460 2
1,110
1,470 2
1,480
1,240
1,190
335
305
345
300
345
230
923
Hydraulic
Loading
withRedrc.
(mdg/acre)
74
84
74
64
58
47
108
108
85
106
100
101
98
82
99
76
85
84
64
64
57
82
Recite.
Rate
(percent)
50
50
60
90
130
140
150
50
60
35
50
60
60
40
60
90
100
110
120
130
95
80
Removal
(percent) .
BOD
272
11
17
14
10
18,
*>
45
17
28
18
3,
242
3
16
8
18
9
18
11
14
-
16
COD

25
17
11
36
172
82
25
6°
282
2
242
4
10
_
122
1
7
13
12
-
14
Removal
(Ib pet day)
BOD
1152
60
95
40
30
45,
3102
130
135
120
20,
ISO2
25
95
45
25
15
30
15
20
-
74
COD

640
300
120
550
170,
ISO2
620
1,090
5902
40
S102
100
190
_
602
5
35
55
60
-
330
NSSC Content
of Combined
BOD
(percent)
70
66
73
83
72
69
66
76
82
83
80
74
90
83
81
89
96
97
100
100
100
82
WITHOUT PRIMARY TREATMENT
3/15
3/12
3/19
3/26
Average
57
63
63
63
62
14
17
17
17
16
275
253
230
280
260
890
990
1,030
890
950
89
106
90
89
93
50
50
65
65
60
9
18
15
11
13
13
19
32
14
20
35
70
50
45
50
270
310
490
190
315
80
71
77
90
79
                'Period allowed for biofflter start up; data not used in evaluation
                      on a single day's data

-------
600
500
             \
                                                          FTT
   T--
                                                                   -f4-4-+
                                                                     -H-
400

300
200
                                                     I MAR*
                                                        GlR^AT
I.S.
1RAJI
                                                    NSSC
                                                         usz
                                                                             H—i-
 100
                      100
                                          200
                                                             300
                                                                                 400
                                                      BIO-FILTRATION BOD,REMOVAL VS.
                                 B005 REMOVED (Ib day)           BOD$LOADING
                                                      TREATMENT OF DOMESTIC WASTEWATER
                                                      AND NSSC PULP AND PAPER MILL WASTES
                                         33
                                                                            FIGURE   IB

-------
with primary treatment a 100 ppd removal could be achieved when the biofilter was loaded
with 400 pounds of  BOD per  thousand  cubic feet  of filter media. Without primary
treatment, the loading must be reduced to 160 pounds of BOD per thousand cubic feet to
achieve the same pounds BOD removed.

Figure 18  also  shows that essentially  no  BOD removal  took place where the  NSSC
percentage was greater than 80 percent. This was independent of the total organic loading to
the biofilter.

The overall treatment efficiency of the biofiltration process can be seen in Table 6.  On an
average the biofilter removed only 16 percent and 13 percent, respectively, of the influent
BOD  with and  without primary treatment of  the raw NSSC waste. The  low removal
efficiency (typical of a high rate "roughing" biofilter) was a result of the high organic and
hydraulic loading of the biofilter.

William Eckenfelder's, Manual of Treatment Processes, cited hydraulic loadings of biofilters
treating other pulp and paper mill process wastes ranging from 90 to 365 mgd/acre for the
Kraft Mill waste and 47 to 189 mgd/acre for black liquor wastes with no recycling. BOD
removal rates at those hydraulic loadings ranged from 10 to 31 percent for the Kraft Mill
wastes and from 58 to 73 percent for the black liquor wastes. The raw wastes in the studies
cited were  diluted, as  witnessed by the influent BOD concentration of 250 mg/1 and 400
mg/1 for the Kraft Mill and black liquor wastes, respectively.

Design criteria for operation of the biofiltration process can be taken directly from  Figure
18. For  example, to remove 100 pounds of BOD per day by biofiltration, it  would be
necessary to load the biofilter at 400 ppd per thousand cubic feet of filter media.

The following conclusions can be made from the biofiltration evaluation:

         1.       The biofilter  functioned primarily as a "roughing" filter at
                  the high hydraulic and organic loadings experienced.

         2.       The "roughing" filter function improved downstream process
                  efficiencies.

         3.       Primary clarification  of the  raw NSSC waste improved the
                  biofiltration efficiency.

         4.       The biofilter  was not effective in removing BOD from the
                  combined wastewater with high percentages (greater than 80
                  percent) of NSSC wastewater.
                                     40

-------
                                   SECTION IX

                      EXTENDED AERATION TREATMENT
The extended aeration system of the pilot plant was comprised of an aeration basin with
diffused air  and a final clarifier with sludge  return. Operation of the system began in
February,  1971, and continued through March, 1972. The performance of the system was
evaluated  by collecting data based upon a  sampling and analytical program carried out
during the study. Variations in NSSC to domestic waste loading, hydraulic flows, aeration
detention  times, temperature, primary treatment, etc., were achieved during the study. The
effects of these conditions on the extended aeration process were evaluated from an
operation and performance standpoint.

Extended aeration was studied in three different arrangements:

         Arrangement No.  1          Pretreatment  with primary clarification
         Arrangement No.  3          Pretreatment  with primary clarification
                                    and biofiltration
         Arrangement No.  4          Pretreatment  by biofiltration

Finally, performance comparisons of each of the three arrangements were made; oxygen
data and sludge production design criteria were developed.
           Extended Aeration with Primary Clarification — Arrangement No. 1

The aeration basin  was  operated with primary clarification from  July,  1971, through
September, 1971. During this period, the percentage of the wastewater loading which was
NSSC BOD loading  ranged from 42  to  100 percent. In addition, attempts were made to
optimize the mixed  liquor volatile suspended solids (MLVSS) at various flows and BOD
loadings. Since BOD loadings could not be determined immediately, flow control was the
primary means of varying the loadings.

Evaluation of the extended aeration process with primary clarification was based upon the
results summarized in Table 7. A comparison of BOD loading to effluent quality is given in
Figure 19. As can to  be from this graph, there appeared to be no significant difference in the
effluent quality for the various percentages of the NSSC wastewater evaluated. It is believed
that the NSSC loadings (which were always greater than 42 percent of the wastewater) were
too high to provide a significant comparison of variation in efficiencies of extended aeration
with NSSC and domestic wastewater influents.
                                    41

-------
to
                                                                           TABLE 7



                                                     EXTENDED AERATION RESULTS - (JULY 14 - AUGUST 26,1971)




                                                                      ARRANGEMENT NO. 1
Operating
Temperature
Date ( C.)
7/14/71
20
21
22
27
28
29
8/10/71
11
12
17
18
19
24
25
26

27
28
28
29
29
29
29
29
28
28
28
29
29
28
28
Percent NSSC
MLVSS Waste Based
(mg/0 on BOD

3,590
3,960
3,980
3,810
3,290
4,120
2,950
3,170
3,460
3,500
3,550
3,950
3,380
3,380
3,440

100
100
96
93
94
83
100
96
100
60
95
93
73
100
100
Oxygen
Transferred1
Ob per day)

33
450
467
480
529
494
562
583
625
591
580
562
556
517
503
BOD Removed
» Influent BOD/MLVSS
(Ib per day) 
-------

•&}-
                                 •
                                                         ,

                                                    BCC
                                                                                 T nr
                                                                       linn :i:
                                                                                  ir
                       02
04
06
                                                              08

                             INFLUENT BOD5 IILVSS ( Ib/d/lb)



                                       43
                                          FIGURE   19

-------
Primary clarification  efficiency had a measurable effect on the extended aeration  basin
process loading versus BOD effluent quality. Prior to entering the aeration basin the VSS of
the clarified and blended wastewater varied from 300 to 410 pounds per day for the  flows
measured. At these loadings the VSS averaged 0.1 pounds per pound of MLVSS. Without
primary clarification  the ratio of VSS of the blended wastewater would be as high as 0.2
pounds per pound of MLVSS. As the ratio of blended influent VSS to MLVSS increased, a
poorer effluent  quality for  a given process loading resulted. This indicates the relative
importance of removing the inert volatile suspended  matter from the  waste prior to its
entering the aeration basin.

The design criteria for the aeration basin may be derived from the graph in Figure 19. For
example, an effluent BOD of 60 mg/1 will require an influent loading of 0.04 pounds of
BOD per pound of MLVSS.

In Arrangement No. 1, it was found that with the process loadings evaluated there was little
measurable difference in efficiency  due to changes in NSSC wastewater  percentages.
Removal of VSS in the primary clarifier provided improved effluent quality at the  same
BOD to MLVSS loading.
   Extended Aeration with Primary Clarification and Biofiltration - Arrangement No. 3

The  aeration  basin was operated with primary clarification of the raw NSSC waste and
biofiltration of the  blended  NSSC-domestic wastewater from October,  1971, to March,
1972. The percentage of NSSC wastewater loading ranged from 44 to 100 percent using
Arrangement No. 3. The hydraulic loadings to the biofilter were varied by changing the
recirculation ratio, and  normally these rates exceeded 40 mgd/acre. In order to maintain
sufficient flow to rotate the trickling filter arm (at 100 percent NSSC wastewater) tap water
was added to the NSSC waste.

The performance of the extended aeration basin under different ratios of NSSC to domestic
wastewater is illustrated by Figure 20. The performance of this process is based upon results
summarized in Table 8. At the range of process  loadings tested,  it  is seen that a poorer
quality effluent resulted with the  100 percent NSSC wastewater  at a given loading. For
example, a process loading of 0.15  pounds of BOD per pound of MLVSS would result in an
effluent BOD of approximately 150 mg/1. On the other hand, the same process  loading
(0.15 Ib BOD/lb MLVSS) would give an effluent BOD of 50 mg/1  in  the case of a blended
NSSC-domestic waste.

The design criteria for the aeration basin under Arrangement No. 3 may be derived from the
graph in Figure 21.  For example, an effluent BOD  of 60 mg/1  will require an influent
loading  of  0.001  pounds  of BOD  per pound of MLVSS for  the 100  percent NSSC
wastewater  and 0.16 pounds of BOD per pound of  MLVSS for  the blended NSSC and
domestic wastewater.
                                    44

-------
300
270
240

  .

                                        0  3
                                                    0 4
                                                                 0 5

                                                                                          0 7
                                  INFLUENT BODK MLVSS  (Ib  d  Ib)




                                            45
FIGURE   20

-------
                        TABLES



EXTENDED AERATION RESULTS - (OCTOBER 13,1971 - MARCH 2,1972)




                   ARRANGEMENT NO. 3
Date
10/13/71
14
20
21
26
27
28
11/2/71
3
4
9
10
16
23
30
12/1/71
7
8
14
15
21
22
28
Operating
Teinpentur
(°C.)
23
25
26
26
24
24
26
25
23
20
16
17
21
16
16
17
18
18
19
21
19
17
17
e MLVSS
(matt
2,240
2,940
3,280
2,960
3,110
3,240
3,200
2,840
3,160
3,420
4,000
3,760
1,920
2,520
2,780
2,940
1,350
1,400
2,640
2,400
1,780
2,160
1,000
Percent NSSC
Watte Bued
on BOD
97
63
72
47
100
67
79
79
82
96
96
57
91
44
87
60
83
97
92
100
58
Oxygen
BODRetnorad
BOD
Tranrfened* Influent BOD/MLVSS Percent
Ob pet day) 
-------
                    TABLE 8 (Continued)






EXTENDED AERATION RESULTS - (OCTOBER 13,1971 - MARCH 2,1972)



                   ARRANGEMENT NO. 3
Date
1/4/72
11
12
13
19
20
25
26
27
2/1/72
2
3
8
9
10
15
16
17
22
23
29
3/1/72
2
Operating
Temperature
16
18
17
19
16
17
IS
16
12
12
11
11
13
12
13
12
12
12
12
11
15
15
16
MLVSS
(mg/0
940
1,880
800
1,660
2,360
2,940
2,960
2,720
2,100
2,300
1,820
2,220
1,260
1,620
1,160
2,740
2,200
2,980
2,580
2,060
1,740
2,060
1,060
Percent NSSC
WuteBued
on BOO
73
52
100
100
79
100
100
67
99
54
56
89
90
72
83
64
61
98
61
85
75
100
66
Oxygen
Trmifened*
(ft per day)

235
-
177
315
222
-
-
—
_
-
-
-
-
-
-
-
-
-
-
-
_

BOD Removed
(tb per day)
544
201
108
292
260
104
71
60
109
119
109
165
87
86
55
92
122
65
93
92
134
41
135
(Ib/ingd)

-
-
-
1,736
780
-
—
—
	
-
1,337
-
608
-
-
-
689
-
-
-
486
-
Influent BOD/MLVSS
(Ib/day/lb)
0.837
0.286
0.412
0.313
0.227
0.140
0.037
0.031
0.063
0.061
0.074
0.092
0.099
0.093
0.117
0.043
0.068
0.028
0.047
0.064
0.097
0.028
0.142
BOD
Percent
Removed
69
37
33
56
49
24
65
72
82
85
81
81
69
57
41
77
82
77
76
70
79
72
89
Effluent
(mg/0
200
293
242
248
220
279
73
73
69
69
91
119
137
211
267
143
129
95
138
189
187
85
87
Excel*
Sludge
(Ib/mvO

_
_
_
280
1,724


-

_
4,198
	
3,336
__
_
_
8,388
_
_
-
6,505

Influent
VSS
(Ib/mjjd)






i_

-


997

1,668
_


1,750


-
166


-------
100
 90
 80
 70
 60
 50
 40
 30
 20
 10
                         ~-/r
                         /
                        t
                     .t.
-£-
                7
              f
                               f
                                 '
                                             •'
                0. 1
             0.2          0.3           0.4          0.5



                 'NFLUENT BOD5  ACTUAL MLVSS  (It)  d  ID)




                               48
                                                                                0.6
                                                                                             0.7
                                                                                    FIGURE  21

-------
              Extended Aeration with Biofiltration - Arrangement No. 4

The  aeration basin  was operated  with biofiltration of  the blended wastewater and
unclarified NSSC wastewaters  during March, 1972. The  percentage of NSSC wastewater
loading ranged from 50 percent to 100 percent using Arrangement No. 4. The effluent from
the biofilter was clarified in the intermediate clarifier.

Performance of the extended aeration process with biofiltration was based upon the results
summarized in Table 9. A comparison of BOD loading to effluent quality is shown in Figure
21. The graph shows no significant difference in effluent quality of the various percentages
of the NSSC wastewater evaluated.

The data in Table 9 does show a slightly lower MLVSS than in Arrangements No. 1 or 3.
This might, in part, be due to the lower VSS loading (approximately 75 pounds/day VSS) to
the aeration basin during Arrangement No. 4.

The design criteria for the aeration  basin under Arrangement No. 4 may be derived from
Figure 21. For example, an effluent BOD of 60 mg/1 will require an influent loading of 0.29
pounds  of BOD per pound of MLVSS for the blended domestic and unclarified NSSC
wastewaters.
                 Performance of Arrangements No. 1, No. 3 and No. 4

The  relative performance of the extended aeration process following primary clarification,
biofiltration and  both  pretreatment  processes,  was  evaluated.  A  comparison of  the
arrangements indicated biofiltration provided the best effluent quality at the highest process
loading. The effluent BOD concentration of 60 mg/1 was used as a comparison figure which
corresponds to approximately 97 percent BOD removal. To  achieve the desired end results
(60 mg/1 BOD) the process loadings would have  to be adjusted for each arrangement as
shown below:

                                              Process Loading          Effluent BOD
Arrangement No.      Description          (Ib  BOD/day/lb MLVSS)          (mg/1)

       1           Primary clarification              0.04                       60
       3           Primary clarification              0.001-0.16               60
                    plus biofiltration
       4           Biofiltration                     0.29                      60


In the case of Arrangement No. 3, the lower limit of the loading range (0.001 Ib BOD/day/lb
MLVSS) provided an effluent of 60 mg/1 when the wastewater was 100 percent NSSC waste.
Temperature variations (11° —  32° C.) were considered to have negligible  effects on the
                                    49

-------
en
O
                                                                       TABLE 9


                                                     EXTENDED AERATION RESULTS - (MARCH 3-29,1972)


                                                                  ARRANGEMENT NO. 4
Date
3/7/72
8
9
14
15
16
21
22
23
28
29
Opmting FwcmtNSSC
Tempentue MLVSS WMto fined
f°CJ (raft on BOD
14
14
13
16
17
18
18
17
15
18
19
1,100
1,380
1,580
620
2,100
1,900
1,860
1,080
1,960
1,640
2,200
60
95
100
86
66
78
85*
77
62
75
100
Oxygen BODR«norad
Tnarfened* I
Obpwdey) Obpef day) Ob/m*0
320
314
278
332
209
201
119
316
275 324
299 318
331 327

2^49
2,256
—
1,356
-
-
-
2,490
-
W13
BOD
nfhMUtBOD/MLVBS Percent Effluent
CIWdty/lb) Renored (mart)
0.341
0.271
0.219
0^39
0.125
0.134
0.087
0311
0.181
0.211
0.171
85
84
80
84
80
79
74
94
91
92
87
45
60
66
49
41
41
40
18
28
26
46
Excew
ShidfB
Ob/mid)

2,565
1,916
-
9^65
—
—
—
7,725
-
4,512
Inflnent
VSS
OWnwO
mm
747
170
-
169
—
—
—
85
—
254
              •Stsndud condtttoni, 5.5 percent tnmfet effldeocy

-------
 aeration process since the BOD loading was maintained well below 0.5 pounds of BOD per
 pound of MLVSS per day. At higher loadings temperature jwould have a noticeable influence
 on the aeration basin effluent quality.
               Extended Aeration Oxygen Requirements and Utilization

 The oxygenation characteristics of the combined NSSC waste and domestic wastewater vary
 with the percentage of NSSC waste based on BOD. These oxygenation characteristics were
 determined for the combined waste with 20 percent and 75 percent NSSC waste.
                                     Alpha (a)

 The alpha (a) coefficient was determined for several different percentages of NSSC and
 domestic wastewater utilizing diffused aeration. The aeration rate was maintained constant
 for tap water aeration and waste aeration for each "a" value determined.

 The alpha (a) values were calculated from the following mathematical derivation:
                                 W = <|c = KLa (C* - C)
                                     dt
 Where           C      =      dissolved oxygen concentration at time t
                 C*     =      equilibrium dissolved oxygen concentration
                 t      =      time
                 W     =      weight of water
                 KLH    =      overall mass transfer coefficient

 The integration of the above equation yields

                 „  _ /2.303 W\ / log <
                 ^La
 where subscripts 1 and 2 refer to measurements at times 1 and 2, respectively.

Since the sample volume was identical for both the tap water and the waste samples, these
expressions of KLa may be simplified to
                                      51

-------
The above equation  may  be solved graphically by plotting (C*  -  C) versus time  on
semi-logarithmic paper and determining the time interval for one cycle.
                 thence

                               (waste)
                  . .  , ,
                 alpha (a) =
                               (tap water)
                                                        tap water
The oxygenation data was evaluated and alpha (a) values for various percentages of NSSC
wastes were  determined. Table  10 correlates the alpha (a) values determined versus the
NSSC percentage of that waste. Figure 22 shows the correlation of alpha (a) versus various
NSSC percentages of the combined waste.
                                      Beta(0)

The beta (0) factor expresses the ratio of the saturation of dissolved oxygen in a waste to
saturation in tap water at given conditions.

The saturation of oxygen in combined NSSC-domestic wastewater was found to vary with
the percentage of NSSC waste. The correlation of beta (0) to the percentage of NSSC waste
is shown in Table 10 and in Figure 22. Figure 22 shows that for several percentages of NSSC
waste evaluated, both alpha and beta decreased  with increasing NSSC percentages of the
wastewater.
                                 Oxygen Utilization

The air applied, temperature and dissolved oxygen of the mixed liquor in the aeration basin
were monitored daily. These data, as well as the alpha (a) and beta (0) values, were utilized
to  evaluate the oxygen requirements of the extended aeration process. All data were
corrected to standard conditions for interpretation. The oxygenation data, given in Table
11, were adjusted to an arbitrary MLVSS concentration of 3,000 mg/1 to permit correlation
of the data.  The oxygen applied relative to BOD removed data is shown graphically in
Figure 23. The curve of best fit for these data indicates the following oxygen requirement at
standard conditions:

                  Oxygen requirement = 0.97 BOD removed + 0.07 MLVSS
                                      52

-------
                           TABLE 10

                     ALPHA (a) AND BETA (0)

                   VS. PERCENTAGE NSSC WASTE
Date
Percentage NSSC Waste
   Based on Flow
L
                                                         Temperature
9/22/71
9/23/71
10/13/71
10/14/71
76
72
18
21
0.42
0.57
0.88
0.65
0.77
0.42
0.93
0.87
29
31
31
23
                             53

-------
60
               0  2
                            0  4
                                         0  6
                                                      0  8
                                                                   1  0
                                                                               1  2
                                   ALPHA (O) AND BETA (j3)  VALUES




                                               54
FIGURE   22

-------
                               TABLE 11
                     O2 APPLIED VS. BOD REMOVED*
Oxygen Applied
Date (Ib per day)
7/20/71
21
22
27
28
29
8/10/71
11
12
17
18
19
24
25
26
10/13/71
14
20
21
26
27
28
17
193
199
199
254
189
301
290
306
286
277
224
259
259
248
460
289
316
367
354
336
334
BOD Removed Oxygen Applied
(Ib oer dav) Date (Ib per day)
61
71
58
73
68
64
91
65
41
69
44
54
57
34
42
309
214
169
200
228
277
210
11/2/71
3
4
9
10
16
23
12/1/71
7
8
14
15
21
22
1/11/72
13
19
20
3/23/72
28
29

376
423
495
421
371
688
670
656
766
746
417
417
711
609
432
344
533
281
601
632
485

BOD Removed
(Ib per day)
105
221
170
221
238
113
208
402
157
123
225
325
184
244
109
150
154
82
148
151
223

*Data corrected to standard conditions and 3,000 mg/l MLVSS
                                55

-------
56
                                FIGURE  23

-------
Additionally, the actual oxygen utilization in the aeration basin was measured on several
occasions in a BOD bottle with a Yellow Springs dissolved oxygen probe. These data, given
in Table 12, were adjusted to an arbitrary MLVSS concentration of 3,000 mg/1 and standard
condition, as shown in Table 13. These data were compared graphically to BOD removed as
shown in Figure 24. The oxygen  utilization curve from Figure 23 was superimposed on
Figure 24.  This superimposition showed the oxygen requirements determined by the two
different methods to be very similar.

The oxygen requirements design criteria for the aeration basin can be taken from Figure 23.
For example, 600 pounds of oxygen per day would be required to remove 400 pounds of
BOD per day.

In summary, design criteria for oxygen requirements were determined  by oxygenation
studies. These included alpha  (a) and beta (0) determinations for various percentages of
NSSC wastes. They also included correlations of oxygen applied versus BOD removed.
                                   Waste Sludge

The excess sludge from the activated sludge facility was estimated  by making a material
balance on the system. The excess sludge was adjusted to an arbitrary flow (1.0 mgd) and an
effluent VSS concentration of 35 mg/1. The quantities of excess sludge were compared to
BOD removed  (Figure 25) and influent VSS (Figure 26). The wide distribution of data
shown in Figures 25 and 26 would not permit a correlation to be made between the BOD
removed or the influent  VSS. As a result, the quantities of excess sludge could not be
estimated from the data collected.

Cellulose fibers are difficult to degrade aerobically and the quantities of excess sludge can be
conservatively estimated as:

     Excess sludge = Influent suspended solids + 0.47 (BOD) removed - Effluent suspended solids

This expression does not reflect the VSS loss due to endogenous respiration. The inert VSS
(cellulose fiber) in the raw settled NSSC waste  will not permit the theoretical endogenous
respiration constant to be applied to MLVSS.

In summary, no  definite  conclusion could be reached as  to the amount of excess sludge
produced from normal operation of the extended aeration process.

The major findings from the extended aeration pilot plant studies are as follows:

          1.       There were no appreciable performance differences due to
                   changes in the percentage of NSSC wastewater. VSS removal
                   of blended influent improved the quality of the effluent at a
                   given unit process loading.
                                      57

-------
I/I
00
                                                    TABLE 12



                                                   O2 UPTAKE

                                              AERATION BASIN DATA
9/21/71
Time
(m3nl
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
—
—
—
—
—
DO
(ma/1)
9
4.5
1.7
0.7
0.3
0.2
0.1
0
—
_
—
—
—
9/21/71
Time
(min)
0
0.5
1.0
1.5
2.0
2.5
—
—
—
—
—
—
—
DO
(mi/I)
9.0
5.5
2.0
0.6
0.1
0
—
—
—
—
—
—
—
9/22/71
Time
(min)
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
DO
9.4
6.7
4.5
2.7
1.3
1.0
0.6
0.4
0.3
0.2
0.2
0.1
0.1
10/14/71
Time.
(min)
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4,0
4.5
_
__
H«_
DO
4.7
2.7
1.8
1.3
1.0
0.8
0.6
0.5
0.2
0
_
_
_
10/14/71
Time
(min)
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
—
_
_
_
DO
6.1
2.9
1.9
1.5
1.1
0.8
0.5
0.1
0
—
—
—
_

-------
                               TABLETS




                      O2 UPTAKE VS. BOD REMOVED*
Date
9/21/71
9/21/71
9/22/71
10/14/71
10/14/71
O2 Uptake x MLVSS (mg/1)
94
281
134
814
1,178
BOD Removed
32
32
211
356
369
(mg/1)





*Data corrected to standard conditions and 3,000 mg/1 MLVSS
                                 59

-------
3.000
2.000
 1 . 000
                    01
                    u.
                  100
                              200
                                           300
                                                        400
                                                                    500
                                          BOD5 REMOVED (Its  d)
                                                60
                                                                                     FIGURE   24

-------
    4  000
    3  500
    3  000
    2  500
!
    2  000
    I  500
    1.000
     500
                      __
                                                                             LJ
                     2 000
4 000        6.000         8  000




    A SLUDGE  OPTIMUM  CONDITIONS  ( Ibs mgd)




                     '
                                                                                       12.000
                                                                                                    14, 000
                                                                                            FIGURE  25

-------
8. 000
7. 000
6. 000
5.000
4 000
3.000
2 000
1 . 000
                 2 000        4 000         6.000         8.000        10 000
                                   SLUDGE  OPTIMUM  CONDITIONS  (IBs mgd)
                                                    62
FIGURE  26

-------
2.       Of the three arrangements tested, biofiltration provided the
         greatest  single improvement  in  effluent  quality of  the
         aeration basin at a given process loading.

3.       Alpha and Beta values depended greatly upon the percentage
         of NSSC wastewater present, and the values ranged from 0.42
         to 0.88 and 0.42 to 0.93, respectively.

4.       Oxygen requirements were determined to be 0.97 pounds per
         pound of BOD removed plus 0.07 pounds of oxygen per
         pound of MLVSS in the aeration basin.
                             63

-------
                                   SECTION X

                             FINAL CLARIFICATION
The separation of the activated sludge from the aeration basin effluent was accomplished
with a clarifier with sludge rakes and a hopper bottom. The clarifier was operated for the
duration of the study-May, 1971, through April,  1972. The unit was evaluated according to
its operating performance at various overflow rates, water temperatures and wastewater
composition.
                                    Operation

The effective size of the final clarifier was 15 feet in diameter with a sidewater depth of
12.9 feet. The unit was operated at different flows to provide variations in overflow rates,
detention times and solids loading. Data was compiled based upon grab samples collected at
sampling locations as shown in Figure 2, and these included the aeration basin effluent, the
clarifier underflow and the final clarifier effluent.

Over the period of operation the activated treatment system encountered different food to
microorganism  ratios,  temperatures,  industrial  wastewater concentrations  and  other
conditions which influenced its performance. These factors also had some effect  on
consistent performance of the final clarifier.
                                    Performance

The results of monthly average performance data on the final clarifier are shown in Table
14. It can be seen that a very high suspended solids removal of 95 percent was achieved over
the study period. In addition, BOD removal was 85 percent. Figure 27 gives the relationship
between the BOD and the total suspended solids removed.

Design considerations are shown in Figure 28. From this figure, it can be seen that increases
in detention time and decreases in overflow rate bring about reductions in the percentage
removal of total suspended solids. It is also shown  that lower temperatures reduce the
performance  of the  clarifier,  i.e., 95  percent  removal  requires an overflow rate of
approximately 1,200 gpd/sq ft at 61° F., where  almost 1,500 gpd/sq ft at 82° F. gives the
same performance. The temperatures of the wastewater should be considered when the final
clarifier is designed.
In the range of NSSC waste to domestic wastewater flows tested, no significant effects on
final clarification were noted.  At  the low loadings of the extended aeration basin it is
believed that settling was enhanced considerably.  At higher food to microorganism ratios
the  settling in the final clarifier would be hampered.
                                      64

-------
                                                        TABLE 14

                                              FINAL CLARIFIER PERFORMANCE
                                                (MONTHLY AVERAGE DATA)
Month
June
July
August
September
October
November
December
January
February
March
Flow w/recirc.
(1,000 gpd)
146
117
168
112
217
210
238
224
167
1%
Overflow
Rate
(gpd/«q ft)
826
662
950
634
1,228
1,188
1,347
1,268
945
1,109
Water
Temperature
79
82
84
86
77
66
64
59
54
61
NSSC Waste
{% Raw Flow)
10
15
17
42
18
16
19
22
24
14
Inlet
TSS
(lb per day)
2,989
4,491
5,678
6,615
6,210
5,657
4,254
4,196
3,242
2,975
Inlet
BOD
(lb per day)
626
579
660
1,185
1,242
1,762
2,062
1,431
1,348
1,353
Removal by Sedimentation Det
TSS BOD Time
(percent) (percent) (min)
93
97
98
99
94
96
91
95
93
94
64
70
87
74
92
97
92
85
91
96
174
216
150
228
120
120
108
114
150
130
Solids
Loading
(lb/sq fyday)
17
25
32
37
35
32
24
24
18
17
Avenge
               180
1,019
71
19
4,631
1,225
                                  95
                                                         85
151
26

-------
10  000
 9 000
 8 000
 7.000
 E 000
 5  000
 4 000
 3 000
 2 000
 1.000
                         /
I
                  '-I-
                                              11
                                              It
                                  ]Q]
                                                                               IRC
IE
                                                                  in v
                                                lit
                                                         1*1
                                                                  FrnrBJSiarnH-iMnip-
                                                                                     vrtt
                 500
                            t  000        1  500        2.000
                                       B005 REMOVED (Ib day)

                                                 66
                                                                2 500
                                                      3.000        3,500
                                                           FIGURE   27

-------
240-1
      1.500
200 -
1. 250-
160 -
1.000-
120 -
        750-
 80-
        500—
 40 -
         250-
  0 -1
            100
                                            TSS REMOVED (PERCENT )
                                                                                         FIGURE   28

-------
                                   SECTION XI

                                COLOR REMOVAL
Paper mill wastewaters are noted for their color problems. The raw wastewater from the
neutral sulfite semichemical pulp and paper waste has a deep brown-black color. Chemical
precipitation  with lime as a coagulant  at various pH levels  has been the most widely
accepted method of color control. However, massive dosages of lime often are required to
produce adequate reductions in color and the process may involve several steps. As a result,
the process requires recalcining of the lime and is usually very expensive.

Laboratory studies were conducted on  various ratios of NSSC and domestic wastewater
using massive lime dosage followed by chlorination. The test procedures and findings are
discussed in depth but the economics of this type of treatment were not investigated in
detail.
                                  Test Procedure

The  color removal  studies were conducted  using a jar test procedure. The wastewater
samples which were studied were composed of NSSC waste, and one part NSSC waste to
one  part domestic wastewater. In the precipitation studies  only hydrated lime was used,
which is native to the Harriman area. The chlorine source for the chlorination studies was
calcium hypochlorite.

The  jar test procedure consisted of dosing batch samples of the wastewater with known
quantities of lime. The wastewater and lime were mixed rapidly for IS seconds, flocculated
slowly for 15 minutes and allowed to  settle. The supernatant was chlorinated after the pH
was  adjusted to neutrality and the color determination was made. After chlorinating,  the
color was again measured by a colorimeter at a pH of 7.
                                     Findings

Findings from the color removal studies are reported in Table 15. These studies include the
massive lime treatment and chlorination. The results of the analyses on different mixes of
NSSC and domestic wastewater are given in Figures 29-32. In Figure 29, it can be seen that
increased dosages of lime on the  NSSC waste  reduced the APHA color significantly. The
lowest color achieved was approximately 7,500 APHA units at 32,000 mg/1 of lime. In the
case of the one to one wastewater mixture, a dosage of slightly more than 22,000 mg/1 gave
the best color quality (Figure 30).
                                       68

-------
           TABLE 15
RESULTS OF COLOR REMOVAL STUDIES
CaO
Dosage
(mg/l)

0
7,570
7,570
7,570
7,570
7,570
7,570
15,140
15,140
15,140
15,140
15,140
15,140
22,710
22,710
22,710
22,710
22,710
22,710
30,280
30,280
30,280
30,280
30,280
30,280
37,850
37,850
37,850
37,850
37,850
37,850
Chlorine
Dosage
(mg/l)

0
0
0
800
600
400
200
0
0
800
600
400
200
0
0
800
600
400
200
0
0
800
600
400
200
0
0
800
600
400
200
PH
(After Treatment)
100 Percent NSSC Wastes
—
11.5
7.0
7.0
7.0
7.0
7.0
11.8
7.0
7.0
7.0
7.0
7.0
11.85
7.0
7.0
7.0
7.0
7.0
12.0
7.0
7.0
7.0
7.0
7.0
12.05
7.0
7.0
7.0
7.0
7.0
Color
at pH 7.0
(APHA Units)

24,250
22,850
17,160
10,350
12,800
14,750
15,850
14,200
12,950
5,940
7,550
10,100
11,275
10,250
9,550
3,900
5,650
8,070
9,100
8,100
7,820
2,015
4,060
6,435
8,110
7,650
8,100
4,350
4,900
5,700
7,500
             69

-------
                            TABLE 15 (Continued)

                   RESULTS OF COLOR REMOVAL STUDIES
 CaO
Dosage
(mg/l)
Chlorine
 Dosage
      PH
(After Treatment)
   Color
  at pH 7.0
(APHA Units)
              50 Percent NSSC Waste-50 Percent Domestic Wastewater
5,680
5,680
5,680
5,680
5,680

  0
7,570
7,570
7,570
7,570
7,570

7,570
7,570
7,570
7,570
7,570
7,570

11,355
11,355
11,355
11,355
11355

15,140
15,140
15,140
15,140
15,140
15,140
 1,000
  800
  600
  400
  200

   0
   0
   0
 1,000
  800
  800

  600
  600
  400
  400
  200
  200

 1,000
  800
  600
  400
  200

   0
   0
  800
  600
  400
  200
      7.0
      7.0
      7.0
      7.0
      7.0

      6.6
      12.2
      7.0
      6.9
      7.0
      7.0

      7.0
      6.9
      7.0
      6.9
      7.0
      6.9

      7.0
      7.0
      7.0
      7.0
      7.0

      12.4
      7.0
      7.0
      7.0
      7.0
      7.0
   1,440
   1,720
   2,800
   5,275
   6,500

   12,200
   7,360
   4,290
   1,120
   1,130
    925

   1,180
   1,815
   2,640
   3,900
   3,960
   4,950

    950
   1,015
   1,150
   2,880
   4,200

   6,250
   3,060
    650
    672
   1,140
   2,930
                                   70

-------
                            TABLE 15 (Continued)

                   RESULTS OF COLOR REMOVAL STUDIES
 Ca O             Chlorine                                            Color
Dosage             Dosage                    pH                     at pH 7.0
(mg/l)	(mg/l)	(After Treatment)	(APHA Units)

              50 Percent NSSC Waste-50 Percent Domestic Wastewater
22,710               0                     12.5                     5,320
22,710               0                      7.0                      2,665
22,710             2,000                    7.0                       189
22,710             1,000                    7.0                       277
22,710              800                     7.0                       630
22,710              800                    12.5                      378
22,710              800                     7.0                       650

22,710              600                     7.0                       638
22,710              600                     7.0                       468
22,710              600                     7.0                       650
22,710              400                     7.0                       830
22,710              400                     7.0                       780
22,710              200                     7.0                      2,600
22,710              200                     7.0                      2,210

45,420             1,000                    8.5                       136
45,420              800                     8.5                       176
45,420              600                     8.5                       240
45,420              400                     8.5                       488
45,420              200                     8.5                      1,440

              15 Percent NSSC Waste-85 Percent Domestic Wastewater

   00                       -                      3,750
  757                0                      9.7                     5,150
 3,785                0                      10.9                      1,470
 5,678                0                       -                       1,160
 7,570                0                      10.6                      1,130
11,355               0                       -                       920
                                    71

-------
FIGURE  29

-------
8. 000
7 000
6 000
la
t-
z
: 5 000
•c
QB
0
-1
U
4 000
3 000
2 000
000
0























































































































































































































































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\






















































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10 000 20 000 30 000
Cat) DOSAGE (mg 1 )
73
FIGURE  30

-------
20.000
18 000
16.000
14 000
12 000
1 0 000
 8.000
 6 000
 4 000
                       s
71
         la )
                                                    (I
                                                            ( aO
 2.0 00
                                                                C 3LJOR HEUIOVALAND
                                                             LIME
                                                                C -ILOF INE
                                                                                NSSfc
                                                             /ASTE
                                                                           3CMESTIC
                                                                                   WAST
                            200
                         400
600
                                     CHLORINE (mg I)
                                                  74
                                                             FIGURE   31

-------
CHLORINE DOSAGE  (mg I)  AT  pH  7  0
                        COLOR REMOVAL AND LIME + CHLORINE:
                             50% NSSC + 50* WASTEWATER
                          TREATMENT OF DOMESTIC WASTEWATER
                          AND NSSC PULP AND PAPER MILL WASTES
                                                     FIGURE   32

-------
Chlorination of the NSSC wastewater after massive lime treatment reduced its color to as
low as 2,000 APHA units. This is shown in Figure 31. A similar reduction is shown by
Figure 32 where the NSSC wastewater diluted with domestic wastewater was reduced to
100 APHA units. In this case, increased chlorination did not bring about further reductions
in color for chlorine dosages above 800 mg/1.

Overall, the lime treatment was very effective and chlorination reduced the color further.
However, based upon the laboratory results, the dosages of lime would be as high as 45,420
mg/1 or up to  190 tons per million gallons of wastewater to be treated. This would require
investigation of a lime reuse process, such as recalcining, in order to determine the economic
feasibility of color removal by this method. Chlorination would appear to be a relatively
small proportion of the total chemical cost of color removal.
                                       76

-------
                                   SECTION xn

                                 DISINFECTION
Disinfection studies on the treated NSSC and domestic wastewater using chlorine and
chloramines were conducted in the laboratory from November, 1971, through March, 1972.
                                    Procedure

Total and fecal coliform analyses using the membrane filter method,  as described in the
13th edition of Standard Methods for the Examination of Water and Wastewater, were run
at the pilot plant site to evaluate effluent disinfection.

The waste entering and leaving the chlorine contact  chamber with no chemicals added was
analyzed for  total and fecal  coliform for one month to establish a  baseline for future
comparison. Then laboratory studies on the effect of chlorine and combination of chlorine
and ammonia application, application sequence and contact time on disinfection were made.
The  contact  time included both the mixing time between the addition of the first and
second chemical, and the mixing time of the combined chemicals and the waste.

The mixing time between the addition of the first and second chemical was varied from 3 to
45 minutes. The mixing time of the combined chemicals and the waste was varied from 5 to
78 minutes. Chlorine followed by ammonia and ammonia followed by chlorine application
sequences were evaluated. Chlorine and ammonia application ranged from 10—40 mg/1 and
0 — 40 mg/1, respectively.
                                      Results

The results of the disinfection studies are shown in Tables 16 through 21. Table 16 shows
the baseline total and fecal coliform determinations. The effects of varying the application
and the application sequence are shown in Tables 17-20. The effects on the effluent of
adding chlorine alone are shown in Tables 20 and 21. The effects of varying the contact
time are shown in Tables 18 and 19.

The contact  time  studies were run concurrently with  application and sequence studies.
Recommended contact times of 5 minutes for the mixing of the waste and ammonia and 15
minutes for the mixing of the combined waste and chemicals after chlorine is added were
reached by choosing those minimal times which resulted in consistent 100 percent coliform
removal. Contact time evaluations were hindered by the fact that other parameters were also
varied during that period.
                                      77

-------
                                                                      TABLE 16

                                                                 DISINFECTION STUDIES
                                                           COLIFORM BASELINE DETERMINATION
00
Influent Pint Chemical Contact Time Second Chemical
Cottfotm Added Concentration Pint Chemical Added Concentration
Count (MPN) (mg/0 andWaite (mgft
Date
10/7/71
10/8/71
10/11/71
10/12/71
10/13/71
10/18/71
10/19/71
10/20/71
10/27/71
Total
28,000
160,000
40,000
24,000
100,000
240,000
36,000
23,000
35,000
Fecal NH3 Cl (mfa) NHj a
No Chemical* Added
120,000
33,000
26,000
18,000
2,000
5,000
11,000
1,000
Contact Time Colifarin Removal
Both Chemfcalf Effluent CoUfoon Efficiency
and Watte Count (MPN) (percent)
(mm) Total
30,000
120,000
28,000
24,000
70,000
240,000
11,000
23,000 .
31,000
Fecal Total Fecal

_
_
- - -
_
_ _
_ _
_ _ -
_ _ _

-------
                                                                        TABLE 17


                                                                  DISINFECTION STUDIES
                                                          APPLICATION AND SEQUENCE EVALUATION
-j
vo
Influent Pint Chemical
Cotifotm Added Concentration
Count (MPN) (mg/0
Date
11/1/71
11/2/71
11/3/71
11/8/71
11/9/71
11/10/71
11/15/71
11/16/71
11/17/71
11/22/71
11/23/71
11/27/71
11/29/71
11/30/71
Total
10,000
38,000
4,000
12,000
4,000
7,000
14,000
12,000
12,000
2,000
16,000
15,000
20,000
6,000
Fecal
12,000
N.D.
56,000
18,000
1,000
800
2,700
30,000
6,000
17,000
29,000
16,000
10,000
7,000
NH3

40
20
40
-
-
-
20
15
-
-
-
8
10
Cl
35
-
-
-
40
30
15
-
-
10
15
15
-

Contact Time
Pint Chemical
and Waste
(min)
3
3
3
3
3
3
3
3
3
3
3
3
3
3
Second Chemical
Added Concentration
(mg/D
NH3
0
-
-
_
0
0
0
-
-
0
0
0
-

a

35
18
20
40
30
15
15
15
10
15
15
15
15
Contact Time
Both Chemicals
and Waste
(min)
68
68
68
72
72
72
78
78
78
46
40
37
41
41
Effluent Collforni
Count (MPN)
Total
5,000
100
400
200
N.D.
700
28,000
3,000
N.D.
5,000
8,000
6,000
10,000
N.D,
Fecal
2,300
N.D,
42,000
N.D,
N.D.
200
140,000
N.D.
N.D,
14,000
16,000
8,000
5,000
N.D.
CoUfoim Removal
Efficiency
(percent)
Total
50
99
90
99
100
90
_
75
100
-
50
60
50
100
Fecal
81
_
100
100
100
75
t —
100
100
18
45
50
50
100
               N.D. - None Detected

-------
                                                                       TABLE 18


                                                                 DISINFECTION STUDIES
                                                  APPLICATION, SEQUENCE, AND CONTACT TIME EVALUATION
00
o
Influent Pint Chemical
CoUform Added Concentration
Count (MPN)
Date
12/1/71
12/6/71
12/7/71
12/8/71
12/13/71
12/14/71
12/15/71
12/20/71
12/21/71
12/27/71
12/28/71
Total
12,000
42,000
12,000
13,000
23,000
8,000
5,000
14,000
6,000
11,000
24,000
Fecal
10,000
54,000
40,000
32,000
10,000
4,000
3,000
N.D.
NJX
N.D.
10,000
(mg/l)
NH3
15
-
-
40
-
-
40
30
30
20
20
a

20
20
—
20
20
-
-
-
-

Contact Time
Pint Chemical
and Waste
(min)
3
3
3
5
5
5
5
5
15
5
20
Second Chemical
Added Concentration
(mgfl)
NH3

20
30
_
40
40
-
-
-
-

a
15
-
-
20
-
-
20
15
15
10
10
Contact Time
Both Chemicab
and Watte
(min)
39
39
55
50
43
41
40
41
44
47
42
Effluent CoUform
Count (MPN)
Total
3,000
26,000
13,000
N.D.
3,000
7,000
15,000
11,000
14,000
6,000
3,000
Fecal
10,000
50,000
27,000
N.D.
N.D.
N;D.
N.D.
N.D.
N.D.
N.D.
N.D.
CoUform Removal
Efficiency
(percent)
Total
75
38
-
100
87
125
-
21
-
45
88
Fecal
N.D.
7
3
100
100
100
100
-
-
-
100
               N.D. - None Detected

-------
                                                                       TABLE 19

                                                                  DISINFECTION STUDIES
                                                   APPLICATION, SEQUENCE, AND CONTACT TIME EVALUATION
oo
Influent Pint Chemical
Colifonn Added Concentration
Count (MPN) (mg/1)
Date
1/3/72
1/4/72
1/5/72
1/10/72
1/11/72
1/12/72
1/17/72
1/18/72
1/19/72
1/24/72
1/25/72
1/26/72
1/31/72
2/1/72
2/2/72
Total
11,000
11,000
20,000
26,000
9,000
27,000
4,000
22,000
40,000
9,000
31,000
6,000
13,000
19,000
4,000
Fecal
20,000
8,000
11,000
1,000
6,000
9,000
1,000
7,000
3,000
N.D.
1,000
1,000
N.D.
2,000
N.D.
NH3 a
40
40
40
40
40
40
40
40
40
20
40
40
40
40
40
Contact Time
Pint Chemical
and Waste
(min)
20
30
45
45
45
45
45
45
45
45
45
45
30
15
15
Second Chemkal
Added Concentration
(mg/l)
NH3 a
20
20
20
20
20
20
20
20
20
40
20
20
20
20
15
Contact Time
Both Chemicab
and Watte
(min)
43
43
43
5
15
15
15
15
15
15
15
15
15
50
51
Effluent CoUfonn
Count (MPN)
Total
N.D.
N.D,
N.D.
6,000
N.D.
N.D.
N.D.
1,000
N.D.
15,000
1,000
300
N.D.
2,800
1,400
Fecal
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
400
N.D.
N.D.
N.D.
N.D.
N.D.
CoUfonn Removal
Efficiency
(percent)
Total
100
100
100
77
100
100
100
95
100
«.
97
95
100
85
65
Fecal
100
100
100
100
100
100
100
100
100
_
100
100
_.
100

               N.D. - None Detected

-------
                                                                         TABLE 20



                                                                   DISINFECTION STUDIES

                                                          EFFLUENT COLIFORM AFTER CHLORINATION
oo
to
Date
2/7/72
2/8/72
2/9/72
2/14/72
2/15/72
2/16/72
2/21/72
2/22/72
2/23/72
2/28/72
2/29/72
Influent Pint Chemical
Colifom Added Concentration
Count (MPN) (mg/1)
Total Fecal NH3 d
- - - 10
- - 10
- - 10
10
- - - 10
- - 10
- - 10
- - - 10
- - - 10
- - 10
10
Contact Time Second Chemical Contact Time
Pint Chemical Added Concentration Both Chemical*
and Waste (mg/0 andWute
(min) NH3 Cl (min)
15 -
15 - -
15 - -
15 - -
15 - -
15 - -
15 - -
15 - -
15 - -
15 -
15 - -
Effluent CoUform
Count (MPN)
Total
32,000
20,000
59,000
19,000
17,000
15,000
20,000
6,000
4,000
8,000
9,000
Fecal
N.D.
N.D.
14,000
N.D.
1,000
N.D.
1,000
1,000
N.D.
2,000
N.D.
CoUform Removal
Efficiency
(percent)
Total Fecal

— —
_ -
- -
— —
- -
_ -
- -
— —
- —

                N.D. - None Detected

-------
                                                                        TABLE 21

                                                                   DISINFECTION STUDIES
                                                          EFFLUENT COLIFORM AFTER CHLORINATION
oo
Date
3/1/72
3/6/72
3/7/72
3/8/72
3/12/72
3/13/72
3/14/72
3/20/72
3/21/72
3/22/72
3/27/72
3/28/72
3/29/72
Influent Fiat Chemical
Cottform Added Concentration
Count (MPN) (mj/0
Total Fecal NH3 Cl
- 10
- ~ 10
10
- - 10
- - 10
- - 10
- _io
_ 10
- 10
_ - 10
- - - 10
- 10
- 10
Contact Time Second Chemical Contact Time
Pint Chemical Added Concentration Both Chemicals
and Watte (mtf 0 and Waste
(mln) NH3 Cl (min)
15 -
15 -
15 -
15 -
15 -
15 - -
15 -
15 -
15 - -
15 -
15 - -
15 -
15 - -
Effluent CoUform
Count (MPN)
Total
2,000
40,000
50,000
4,000
20,000
24,000
7,000
6,000
4,000
60,000
50,000
500
30,000
Fecal
2,000
28,000
1,000
2,000
35,000
68,000
N.D.
2,500
300
4,000
8,300
1,100
1,900
Conform Removal
Efficiency
(percent)
Total Fecal

— _
— —
_ —
— —
_ _
c
_ —
- -
- -
_ _
- -

                N.D. - None Detected

-------
An example comparing the application sequences from Tables 17-20 with concentration
of ammonia and chlorine held constant is shown below:

 Date                Application Sequence                 Total             Fecal
12/13/71
12/14/71
1/3/72
1/4/72
Chlorine followed by ammonia
Chlorine followed by ammonia
Ammonia followed by chlorine
Ammonia followed by chlorine
87
125
100
100
100
100
100
100
 This data shows that the ammonia followed by chlorine application sequence was more
 effective in disinfection.

 The amount of chlorine necessary to achieve 100 percent coliform removal is 40 mg/1 as
 shown in Table 17, on November 9, 1971. The amount of ammonia plus chlorine necessary
 to achieve 100 percent coliform removal is 40 mg/1 ammonia plus 20 mg/1 chlorine as shown
 in Table 19 on January 3 and 4, 1972. According to current market prices for chlorine and
 ammonia,  the combination of ammonia and chlorine  is less expensive  than the higher
 amount of chlorine. Thus, the combination of chlorine  and ammonia  should be more
 economical.

 In conclusion, the disinfection studies showed  that the following procedure  is the  most
 effective and economical in removing total and fecal coliform organisms:

          1.       Add ammonia at 40 mg/1 and allow  at least a 5-minute
                   contact time.

          2.       After  the   5-minute  contact  time,  chlorinate  at  a
                   concentration of 20 mg/1.

          3.       Allow at least a 15-minute contact time.

          4.       Discharge as effluent.
                                       84

-------
                                  SECTION xm

                           DESIGN CONSIDERATIONS
In the following subsections the design considerations are summarized and reviewed from an
individual  process  and total  treatment  system standpoint.  Emphasis was  placed upon
performance,  maintenance, design factors, and other items which were  believed  to be of
particular importance  as a result of this pilot plant study. The processes covered included
primary clarification, biofiltration, extended aeration, final clarification and disinfection.
                      Primary Clarification of NSSC Wastewater

Due to the high cellulose concentration in  the raw  NSSC wastewater the VSS were
correspondingly high. Difficulty in  removing the cellulose  as VSS was one of the most
significant factors in primary clarifier design.

Overflow rates from 200  to 300 gpd/sq ft resulted in  average suspended solids removal
efficiencies from 45  to 76 percent. Constant plugging by solids in piping and valves made
sludge drawoff difficult and resulted in  lower suspended solids removal efficiencies. Only
minimal BOD and COD removals were achieved in the primary clarifier and these removals
were almost independent of the suspended solids removal.
                                    Biofiltration

The performance of unit processes within the pilot plant treatment system was strongly
influenced by the high rate biofilter.

From a design viewpoint, the biofilter influent BOD and COD were reduced an average of
only 13 to 16 percent with biofilter loadings averaging 260 to 290 pounds of BOD per day
per thousand  cubic  feet of filter media.  Primary clarification  of the NSSC wastewater
improved the biofilter BOD removal performance by approximately 100 percent. Increased
proportions of NSSC wastewater reduced the performance  of the filter to  almost zero.
However, comparison of operating results of the extended aeration basin with and without
the  biofilter  markedly  changed  the  extended  aeration  design  requirements.  Design
consideration  for the biofilter should be based on the effect  it has on the performance of
the extended aeration process and not on the reductions in BOD.
                                 Extended Aeration

 It was concluded in Section IX of this report that optimal extended aeration efficiency
 occurred  when the raw  NSSC waste was clarified .and the combined NSSC-domestic
 wastewater was treated by biofiltration.
                                       85

-------
The process loadings, i.e., pounds of BOD per pound of MLVSS per day, should be less than
0.2 to obtain desirable  effluent quality. Also, as long as this loading is maintained, the
temperature will have little effect on the removal efficiency of the aeration basin.

The  nutrients in  the combined NSSC-domestic wastewater were sufficient to  maintain
biological activity in the aeration basin.

A range of 200 to 10,000 pounds of excess sludge was produced when 500 to 3,500 pounds
of BOD were removed per day. This depended largely on the aeration basin influent VSS of
the NSSC  waste.  Variations in the recirculation ratio of 5 to 75 percent did not affect
significantly the aeration basin efficiency.

Oxygen requirements for the extended aeration basin can be taken from Figure 23 where it
is shown that approximately two  to  three pounds of oxygen are required to remove one
pound of BOD in the aeration basin. This relatively high oxygen demand was  probably
caused in part by the high oxygen demand of the sulfites in the NSSC waste.
                                 Final Clarification

The effects of several operating conditions on solids settling were demonstrated.

The following operating parameters were maintained:

       Operating Parameters                          Range of Values

         Overflow Rate                        600 to 1,300 gpd/sq ft
         Process Loading                      0.1 to 0.2 Ib BOD/lb MLVSS/day
         Detention Time                      1.5 to 4 hours
         Temperature                         54° to 86° F.

As a result, the final clarifier operated at a 91 to 99 percent TSS removal efficiency and 64
to 97 percent BOD removal.
                                    Disinfection

The best disinfection results were achieved through the addition of 40 mg/1 ammonia and 20
mg/1 chlorine. The contact time after the addition of ammonia was at least 5 minutes. After
the addition of chlorine, the contact time was 15 minutes prior to discharge.
                                       86

-------
                                  SECTION XIV

                              ACKNOWLEDGMENTS
Mr. Stanley D. Kelley, Manager of the Harriman  Utility Board, is acknowledged for his
support throughout the project. Mr. Amos G. Stuehser, Superintendent of Water and Sewer
Systems, Harriman Utility Board,  was Project Director. Mr. Stuehser and associates are
acknowledged for analytical work and operation of the pilot plant.

The  pilot plant faculty  was designed by  Black,  Crow  and Eidsness, Inc., Consulting
Engineers, under the guidance of Dr. James B. Goodson and Mr.  Robert E. Rader. Project
coordination and technical assistance were provided by Mr.  Philip J. Farrell and his staff at
Black, Crow and Eidsness, Inc.

The support of the project by the Water Quality Office, Environmental Protection Agency
and the assistance provided by Mr. Edmond Lomasney as Project Officer is acknowledged
with sincere thanks.
                                       87

-------
                                  SECTION XV

                                 REFERENCES
Brosig, A. Jr., et al, "Activated Sludge Joint Treatment of Pulp and Paper Effluent with
         Municipal Sewage," TAPPI, 54, 386 (1971).

Eckenfelder, William W., Industrial Water Pollution Control, McGraw-Hill Book Co., New
         York.N. Y. (1966).

Eckenfelder, William W., Manual of Treatment Processes, Water Resource Management
         Series, Vol. 1(1968).

Florida State Board of Health, Sewage Guide, 51-62 (1970).

Harnmerhill Paper Company and Erie, Pennsylvania, Joint Municipal and Semichemical
         Pulping Waste Treatment, (July, 1969).

Spruill, E.L., "Paper Mill Waste: Treatment for Color Removal," Water and Sewage Works,
         Vol. 118, No. 3, 82 (1971).

Wuhrmann, K., Advances in Biological Waste Treatment, Peigamon Press, Oxford (1963).
                                        89

-------
                                   SECTION XVI

                              GLOSSARY OF TERMS


Acid — A compound which dissociates in water to form hydrogen ions.

Activated  Sludge — A flocculent assemblage of microorganisms, non-living organic matter
and inorganic materials.

Aeration — Process of intimate contact between air and liquid device.

Aerobic — Living only in the presence of free oxygen.

Alkalinity  — The  ability of a water to  accept  proton, usually due to  the presence of
bicarbonate, carbonate and/or hydroxide.

Bacteria — One-celled microscopic organisms.

Batch Process — A process in which there is no inflow or outflow.

Biochemical Oxygen  Demand (BOD) -  The quantity of oxygen utilized in the biochemical
oxidation  of organic matterin 5 days at 20° C.

Biological Oxidation  - A biochemical reaction in which materials combine with oxygen to
produce energy.

Buffer — A substance in solution which makes the solution more resistant to pH changes.

Chemical  Oxygen  Demand (COD)  — The amount  of oxygen required for the chemical
oxidation of organics in a liquid.

Chlorinator - A machine for feeding either liquid or gaseous chlorine to a  stream of water.

Clarifier - A tank for separating solids in suspension by settling out.

C/N Ratio - The weight ratio of carbon to nitrogen in an organic system.

Coliform Organisms — A group of bacteria recognized as indication of fecal pollution.

Colorimetric  Determination  -  An analytical  procedure  based on  measurement, or
comparison with standards, of color naturally present in samples or developed therein by
addition of reagents.
                                        91

-------
Dehydrated — Free from or lacking water.

Dilution Rate — Reciprocal of retention time.

Dissolved Matter — The material in solution in a liquid.

Dissolved Oxygen (DO) — Oxygen not combined with other chemicals in water.

Effluent — A liquid, solid  or gas, frequently waste, discharged or emerging from a process.

Endogenous Respiration — An auto-oxidation of cellular material that takes place in the
absence of assimilable organic material to furnish the energy required for the replacement of
worn-out components of protoplasm.

Equalizing Basin —  A holding  basin  in which,  by retention,  variations in flow and
composition of a liquid are averaged out.

Filtrate —  The liquid which has passed through a filter.

Filtration  — The process of separating solids from a liquid by means of a porous substance
through which only the liquid passes.

Floe — A felted mass  formed in a liquid medium by the aggregation of a number of fine
suspended particles.

Flow Diagram — The diagrammatic representation of a works process, showing the sequence
and interdependence of the successive stages.

Flumed — The transportation of solids by suspension in flowing water.

Hydrolysis — A chemical reaction in which a compound reacts with the ions of water (H +-
OH") to form a weak acid, a weak base or both.

Limiting Nutrient — That nutrient of which the concentration in the substrate limits the
growth of the organism utilizing the substrate.

Mixed  Liquor — Mixture of activated sludge and liquid waste.

Mixed  Liquor Suspended Solids (MLSS) — Filterable material contained in mixed liquor.

Mixed  Liquor Volatile Suspended Solids (MLVSS) — Filterable material in mixed liquor
which will ignite when exposed to 550° C. for one hour.

Nutrient  —  Any substance assimilated  by  organisms which  promotes growth and
replacement of cellular components.
                                         92

-------
Oxidation — Reaction of a substance  with oxygen loss of electrons by one element to
another element.

Pathogenic — Causing disease.

Residue — That which remains after a part has been separated or otherwise treated.

Sedimentation — Gravitational settling of solid particles in a liquid system.

Supernatant — The liquid standing above a sediment or precipitate.

Thickening Tank — A sedimentation tank for concentrated suspensions.

Total Suspended Solids (TSS) — Total filterable solids in a sample.

Total Residue — Total dissolved and suspended solids in a sample.

Turbidity -  The reduction of transparency of a  liquid  due to the scattering of light by
suspended particles.

Unit  Operation -  A physical  process which  can be  clearly  distinguished from other
processes by the  fundamental  principles involved.  Unlike most unit  processes,  unit
operations can be formulated in rather precise mathematical expressions.

Unit  Process - A chemical or biological process  which can be clearly  distinguished from
other processes by the fundamental principles involved.


                                       Symbols

     C       =    Dissolved oxygen concentration at time, t
     C*      =    Equilibrium dissolved oxygen concentration
      t        =    time
     W       =    Weight of water
      KLa     =    Overall mass transfer coefficient

      a       =    KLH (waste)

                   KLa (taP water)
      0       =    Ratio of saturation of DO in a waste to saturation of DO in
                   tap water at a given concentration
                                           93

-------
                              SECTION XVH
                                APPENDIX

Table Number                                                       Page Number
  A-1          Monthly Summary of Results of Overall Plant
               Operation                                                96
  A-2          Monthly Influent Wastewater Characteristics                   97
  A-3          Primary Treatment - Blend Tank (S-5) Effluent                99
  A-4          Secondary Treatment — Aeration Basin                      101
  A-5          Secondary Treatment - Aeration Basin Effluent               102
  A-6          Secondary Treatment - Final Clarifier (S-9)                  103
  A-7          Secondary Treatment - Chlorine Contact Chamber (S-10)      104
                                       95

-------
                                                   TABLE A-l
                           MONTHLY SUMMARY OF RESULTS OF OVERALL PLANT OPERATION*
Plant Influent
BOD Loading1
flb/davl
Date
1971
March
April
May
June
July
August
September
October
'November
December
1972
January
February
March
Ind.

	
186
188
177
201
201
304
323
255
478

423
365
302
Dom.

90
103
88
151
94
104
15
153
119
118

78
12
89
COD Loading1
(Ib/dav^l
Ind.

	
397
936
1,055
1,455
1,475
2,109
1,812
1,224
1,917

1,646
1,732
1,272
Dom.

243
260
229
435
286
302
61
409
302
345

189
31
272
PH

7.6
7.3
7.2
7.3
7.5
7.5
7.6
7.4
7.2
7.3

7.3
7.2
7.1
BOD Loading
(ib/day)

62
111
109
127
102
111
243
189
99
309

285
62
86
Chlorine Contact Chamber Effluent (S-10)
COD Loading
(Ib/day)

203
578
740
905
878
952
1,008
1313
976
1,535

1,247
348
766
Total
P04
(mg/1)

20
23
14
18
18
29
13
-
20
11

7
6
12
NH3 N03 N-Org. SS
(mg/1) (mg/1) (mg/1) (mg/1)

10.0 0.5 5.6
13.0 N.D. 10.5 295
144
170
141
121
- 154
264
- -497
- - 269

3.4 2 13.6 198
229
90
'Unclarified Waste
*Values represent monthly averages
N.D. - None Detected

-------
                                              TABLE A-2

                          MONTHLY INFLUENT WASTEWATER CHARACTERISTICS*
BOD Loading1
(Ib/day)
Date
1971
March
April
May
June
July
August
September
October
November
December
1972
January
February
March
Ind.

—
186
167
128
204
213
350
379
281
474

510
395
335
Dom.

90
102
88
151
94
104
15
153
119
118

78
12
89
COD Loading1
(Ib/day)
Ind.

—
397
240
—
—
—
—
1,671
1,122
2,025

1,893
1,481
1,173
Dom.

243
260
229
435
286
302
61
409
302
345

189
31
272
pH
Ind.2

6.7
6.9
6.9
6.9
6.9
6.7
6.6
6.8
6.8
6.8

6.6
6.9
6.8
Dom.

7.1
7.0
6.8
6.9
7.0
6.8
6.8
6.8
6.7
6.9

6.9
6.9
6.8
Ortho PO4 (mg/1)
Ind.2

4
6
6
4
4
5
6
—
5
3

3
4
3
Dom.

14
18
19
31
28
34
28
—
24
12

8
—
12
Total PO4 (mg/1)
Ind.2

10
10
10
8
11
13
12
—
13
8

10
17
10
Dom.

23
24
20
29
29
36
32
—
33
20

19
—
18
1 Clarified Waste
2 Unclarified Waste
*Values represent monthly averages
N.D. - None Detected

-------
                                        TABLE A-2 (Continued)

                         MONTHLY INFLUENT WASTEWATER CHARACTERISTICS*
Date
1971
March
April
May
June
July
August
September
October
November
December
1972
January
February
March
NH,
Ind.1

0.5
N.D.
0.1
1.0
5.2
2.7
1.6
—
—
—

—
—
—
(mg/1) NO,
Dom. Ind.1

12.0
19.7
18.3 N.D.
22.4 N.D.
23.0 N.D.
14.5
19.2 26
— —
_ _
— —

_ _
— _
— —
(mg/1)
Dom.

0.3
N.D.
N.D.
N.D.
N.D.
—
2.8
—
—
—

—
—
—
N-Org. (mg/1)
Ind.1

^
27.1
31.6
34.9
55.1
27.3
29.3
—
_
—

—
—
—
Dom.

7.0
11.1
8.9
9.4
9.1
8.6
7.0
—
—
—

—
—
—
Total Solids
(mg/1)
Ind.1

_
11,682
12,040
12,303
11,621
13,637
13,362
12,315
12,628
11,229

9,735
10,584
10,386
Dom.

_
427
401
499
501
615
528
551
562
444

394
432
382
Suspended Solids
(mg/1)
Ind.1

_
2,140
3,139
3,544
3,649
3,900
3,639
1,488
1,116
1,527

864
1,043
1,430
Dom.

_
83
36
63
83
79
76
78
105
52

70
86
40
^nclarified Waste
"Values represent monthly averages
N.D. - None Detected

-------
\O
                                                      TABLE A-3

                                   PRIMARY TREATMENT - BLEND TANK (S-S) EFFLUENT*
Date
1971
March
April
May
June
July
August
September
October
November
December
1972
January
February
March
pH

_
—
7.3
7.2
7.2
7.1
7.1
7.2
7.1
7.2

7.2
7.4
7.2.
BOD
(mg/1)

...
—
333
223
264
237
1,266
439
431
514

510
616
371
COD
(mg/1)

	
—
1,035
1,281
1,362
1,376
5,105
1,594
1,665
1,689

1,573
1,848
1,307
Ortho
P04
(mg/1)

	 L
—
19
21
17
14
5
—
14
9

7
1
7
Total
PO4 NHj
(mg/l) (mg/1)

._.., ..
— —
15 17.3
19 22.5
16 22.8
17 12.4
8 9.0
— —
18
11

10
5
11
N03
(mg/l)

_
—
N.D.
N.D.
N.D.
—
13
—
—
—

—
_

N-Org.
(mg/l)

_
—
13.7
10.0
12.7
9.7
18.7
—
_
—

—
—

          •"Values represent monthly averages
          N.D. - None Detected

-------
                                         TABLE A-3 (Continued)

                          PRIMARY TREATMENT - BLEND TANK (S-5) EFFLUENT*
Date
1971
March
April
May
June
July
August
September
October
November
December
1972
January
February
March
Total
Solids
(mg/1)

—
—
1,638
1,282
1,764
2,008
6,823
1,989
1,976
2,238

2,031
2,827
1,665
Volatile
Solids
(mg/1)

—
—
Ill
612
881
941
2,717
888
885
872

859
963
727
Suspended
Solids
(mg/1)

	
—
380
170
278
312
1,210
123
191
243

158
110
140
Retention
Time(hr)

0.430
0.425
0.380
0.290
0.410
0.460
0.280
0.420
0.300
0.300

0.560
0.300
0.320
Nutrient
NH3 (Ib)

—
—
6.4
—
—
—
20.9
12.0
—
—

—
8.5
9.9
Feed
NH3 (ppm)

—
—
6.8
_
—
—
70
11.8
—
—

—
10.6
10.0
"Values represent monthly averages
N.D. - None Detected

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                                             TABLE A-4
                              SECONDARY TREATMENT - AERATION BASIN*
Date
1971
March
April
May
June
July
August
September
October
November
December
1972
January
February
March
Retention
Time (hr)

13.8
15.0
25.0
21.2
26.0
30.5
67.1
25.6
29.5
20.2

22.6
30.3
22.7
SLR1
(Ib BOD/lb
MLVSS/day)

	
—
—
0.14
—
—
0.08
0.13
0.09
0.27

0.37
0.07
0.21
D.O.
Influent
(mg/1)

1.80
0.30
N.D.
0.10
0.19
0.11
0.64
0.77
0.65
—

2.90
2.70
2.20
Oa
Applied
(Ib)

—
9,709
12,740
10,920
11,160
12,650
12,700
13,468
14,720
13,826

11,590
14,100 .
12,600
ss
(mg/1)

145
553
899
2,448
4,591
4,050
7,069
3,430
3,233
2,146

2,240
2,328
1,820
vss
(mg/1)

ai_
—
622
2,068
3,237
3,402
5,509
2,915
3,107
1,959

1,870
2,045
1,580
1 Sludge Loading Rate
•"Values Represent Monthly Averages
N.D. - None Detected

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                                            TABLE A-5

                        SECONDARY TREATMENT - AERATION BASIN EFFLUENT*
Date
1971
March
April
May
June
July
August
September
October
November
December
1972
January
February
March
pH

7.5
7.3
7.3
7.2
7.4
7.4
7.5
7.2
7.2
7.2

7.2
7.2
7.1
BOD
(mg/i)

84
179
330
513
592
471
1,266
686
1,007
1,040

764
968
828
COD
(mg/1)

290
722
1,770
3,339
5,400
5,567
8,514
4,974
3,766
3,536

2,973
3,694
3,015
Ortlio
PH4
(mg/1)

14
21
22
34
23
20
16
—
16
9

7
2
8
Total
P04
(mg/1)

23
25
20
46
37
25
21
—
24
16

12
10
16
NH,
(mg/1)

10.0
16.0
5.2
12.6
10.1
5.4
4.4
6.8
9.3
11.4

3.2
6.0
7.6
NO,
(mg/1)

0.7
N.D.
N.D.
0.8
0.1
—
12.0
5.6
3.0
2.0

2.0
1.5
1.8
N-Org.
(mg/1)

7.5
8.2
17.0
28.0
24.2
15.7
34.9
71.0
172.0
104.2

48.2
79.4
29.2
Fixed
Solids
(mg/1)

—
—
433
—
—
1,513
—
1,294
1,363
1,250

—
—
~*~"
Total
Solids
(mg/1)

462
1,124
2,066
3,646
6,490
5',640
—
4,263
4,647
3,622

3,482
3,812
2,658
"Values represent monthly averages
N.D. - None Detected

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                                                       TABLE A-6
                                     SECONDARY TREATMENT - FINAL CLARIFIER (S-9)*
8
Date
1971
March
April
May
June
July
August
September
October
November
December
1972
January
February
March
Retention
Time (hr)

1.9
2.1
3.7
3.0
3.7
2.6
4.3
1.9
2.1
1.8

1.9
2.7
2.2
pH

7.5
7.3
7.3
7.2
7.4
7.4
7.6
7.2
7.2
7.3

7.3
7.2
7.1
Ortho PO4
(mg/1)

14
19
16
21
20
18
11
—
13
8

6
0.6
8
Total PO4
(mg/1)

22
22
14
18
16
21
13
—
19
10

10
5
11
NH,
(mg/1)

12.0
14.6
7.6
12.0
16.5
5.2
4.8
8.3
9.3
8.7

2.7
4.9
8.0
NO3
(mg/1)

0.4
0.3
—
0.9
0.1
—
19.0
5.6
3.0
2.0

2.0
1.7
2.3
N-Org.
(mg/1)

6.3
8.0
17.4
11.5
13.1
9.0
17.3
21.5
24.6
18.0

13.9
23.1
11.4
VS
(mg/1)

— .
525
588
550
699
766
1,866
705
571
684

643
881
418
SS
(mg/1)

—
308
237
186
156
175
192
286
276
294

200
284
150
           "Values represent monthly averages

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g
                                                      TABLE A-7

                               SECONDARY TREATMENT - CHLORINE CONTACT CHAMBER (S-10)*
Date
1971
March
April
May
June
July
August
September
October
November
December
1972
January
February
March
Retention
Time (hr)

1.00
1.00
0.90
0.77
0.96
1.10
2.40
0.90
1.03
0.71

0.81
1.10
0.78
pH

7.6
7.3
7.2
7.3
7.5
7.5
7.6
7.4
7.2
7.3

7.3
7.2
7.1
BOD
(mg/1)

7.3
124
115
108
111
131
760
183
95
254

274
254
95
COD
(mg/1)

240
646
766
763
1,023
1,147
3,009
1,305
1,078
1,276

1,258
1,450
822
Ortho
P04
(mg/1)

12
19
15
23
22
22
11
—
17
10

6
0.4
8
Total
PO4 NHa NOj N-Org.
(mg/1) (mg/1) (mg/1) (mg/1)

20 10.0 0.5 5.6
23 13.0 N.D. 10.5
14
18
19
29
14
— — ' — —
20
11

7 3.4 2.0 13.6
6
12
SS
(mg/D

	
295
144
170
141
121
154
264
497
269

198
229
90
Fixed
Solids
(mg/1)

_,_„,
53
72
64
78
93
290
90
95
101

106
138
69
           ""Values represent monthly averages
           N.D. - None Detected

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                               Subjeri Fn M fit Group
                               05D
                                               SELECTED \VATicR  RESOURCES ABSTRACTS
                                                       INPUT TRANSACTION  FORM
 J  i                         Harriman Utility Board
                             Harriman, Tennessee

 6  i T"'e Treatment of Domestic Wastewater and NSSC Pulp and Paper Mill Wastes
 ]Q \Authorfs)
	'  P. J. Farrell
      L. R. Heble
      A. G. Steuhser
                                   16
Project Designation
   EPA Project No. 11060 DBF
                                   21
                                       Note
                                          A short appendix cohering the pilot plant's operational
                                          parameters and results will be made available upon request.
 22
     Citation
           Environmental  Protection Agency report number,
           EPA-660;2-73-010, December  1973.
 23
Descriptors (Starred First)
  *Domestic Waste, *Neutral Sulfite Semichemical (NSSC) Pulp and Paper Mill Waste, *PiIot Plant,
  Primary Clarification, Biofiltration, Extended Aeration, Final Clarification, Disinfection
 25
Identifiers (Starred First)
  Joint Treatment, Organics Removal, Solids Removal, Color Removal
 27  Abstract
           The Harriman Utility Board and the Mead Corporation made a study of the joint treatment of
       primary clarified domestic waste and neutral sulfite semichemical (NSSC) pulp and paper mill wastes.
       A pilot plant was constructed and operated from April, 1971 through March,  1972.

           The most effective treatment scheme consisted of a biofilter (used as a roughing filter) and an
       extended aeration system. Color reduction was accomplished by massive lime and chlorine additions
       due to the color's dependency on pH.  Disinfection was optimum when ammonia was mixed with the
       combined wastes prior to chlorination.

           The biofilter's BOD removal efficiency ranged from 3 to 45 percent. Extended aeration's BOD
       removal efficiency ranged from 24 to 98 percent.

           This report was submitted in fulfillment of Research and Development Grant No. 11060-DBF
       between the Environmental Protection Agency and the Harriman Utility Board, Harriman, Tennessee.
          p_J-Farreli
                                       Harriman utility Board, Harriman, Tennessee
  WR:I02 (REV  JULV 19691
  «RSIC
                                               SEND TO' WATER RESOURCES SCIENTIFIC INFORMATION CEf
                                                       U S DEPARTMENT OF THE INTERIOR
                                                       WASHINGTON. D C J0340
                                                                  US. GOVERNMENT ff.OmtS SHCt IS/4- X6->U/19S

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